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    camera is an instrument used to capture and store images and videos, either digitally via an electronic image sensor, or chemically via a light-sensitive material such as photographic film. As a pivotal technology in the fields of photography and videography, cameras have played a significant role in the progression of visual arts, media, entertainment, surveillance, and scientific research. The invention of the camera dates back to the 19th century and has since evolved with advancements in technology, leading to a vast array of types and models in the 21st century.

    Cameras function through a combination of multiple mechanical components and principles. These include exposure control, which regulates the amount of light reaching the sensor or film; the lens, which focuses the light; the viewfinder, which allows the user to preview the scene; and the film or sensor, which captures the image.

    Several types of camera exist, each suited to specific uses and offering unique capabilities. Single-lens reflex (SLR) cameras provide real-time, exact imaging through the lens. Large-format and medium-format cameras offer higher image resolution and are often used in professional and artistic photography. Compact cameras, known for their portability and simplicity, are popular in consumer photography. Rangefinder cameras, with separate viewing and imaging systems, were historically widely used in photojournalism. Motion picture cameras are specialized for filming cinematic content, while digital cameras, which became prevalent in the late 20th and early 21st century, use electronic sensors to capture and store images.

    The rapid development of smartphone camera technology in the 21st century has blurred the lines between dedicated cameras and multifunctional devices, as the smartphone camera is easier to use, profoundly influencing how society creates, shares, and consumes visual content.

    History

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    Main article: History of the camera

    19th century

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    Beginning with the use of the camera obscura and transitioning to complex photographic cameras, the evolution of the technology in the 19th century was driven by pioneers like Thomas WedgwoodNicéphore Niépce, and Henry Fox Talbot. First using the camera obscura for chemical experiments, they ultimately created cameras specifically for chemical photography, and later reduced the camera’s size and optimized lens configurations.

    The introduction of the daguerreotype process in 1839 facilitated commercial camera manufacturing, with various producers contributing diverse designs. As camera manufacturing became a specialized trade in the 1850s, designs and sizes were standardized.

    The latter half of the century witnessed the advent of dry plates and roll-film, prompting a shift towards smaller and more cost-effective cameras, epitomized by the original Kodak camera, first produced in 1888. This period also saw significant advancements in lens technology and the emergence of color photography, leading to a surge in camera ownership.[1][2][3]

    20th century

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    The first half of the 20th century saw continued miniaturization and the integration of new manufacturing materials. After World War I, Germany took the lead in camera development, spearheading industry consolidation and producing precision-made cameras. The industry saw significant product launches such as the Leica camera and the Contax, which were enabled by advancements in film and lens designs. Additionally, there was a marked increase in accessibility to cinematography for amateurs with Eastman Kodak’s production of the first 16-mm and 8-mm reversal safety films. The World War II era saw a focus on the development of specialized aerial reconnaissance and instrument-recording equipment, even as the overall pace of non-military camera innovation slowed.

    In the second half of the century, Japanese manufacturers in particular advanced camera technology. From the introduction of the affordable Ricohflex III TLR in 1952 to the first 35mm SLR with automatic exposure, the Olympus AutoEye in 1960, new designs and features continuously emerged. Electronics became integral to camera design in the 1970s, evident in models like Polaroid’s SX-70 and Canon’s AE-1.

    Transition to digital photography marked the late 20th century, culminating in digital camera sales surpassing film cameras in the United States by 2003. In contrast, the film camera industry in the UK, Western Europe, and the USA declined during this period, while manufacturing continued in the USSR, German Democratic Republic, and China, often mimicking Western designs.[1][2][3]

    21st century

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    The 21st century witnessed the mass adoption of digital cameras and significant improvements in sensor technology. A major revolution came with the incorporation of cameras into smartphones, making photography a commonplace activity. The century also marked the rise of computational photography, using algorithms and AI to enhance image quality. Features like low-light and HDR photography, optical image stabilization, and depth-sensing became common in smartphone cameras.[4][5][6]

    Mechanics

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    Basic elements of a modern digital single-lens reflex (SLR) still camera

    Most cameras capture light from the visible light spectrum, while specialized cameras capture other portions of the electromagnetic spectrum, such as infrared.[7]: vii 

    All cameras use the same basic design: light enters an enclosed box through a converging or convex lens and an image is recorded on a light-sensitive medium.[8] A shutter mechanism controls the length of time that light enters the camera.[9]: 1182–1183 

    Most cameras also have a viewfinder, which shows the scene to be recorded, along with means to adjust various combinations of focus, aperture and shutter speed.[10]: 4 

    Exposure control

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    Main article: Exposure (photography)

    Aperture

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    Main article: Aperture

    Different apertures of a lens

    Light enters the camera through an aperture, an opening adjusted by overlapping plates called the aperture ring.[11][12][13] Typically located in the lens,[14] this opening can be widened or narrowed to alter the amount of light that strikes the film or sensor.[11] The size of the aperture can be set manually, by rotating the lens or adjusting a dial or automatically based on readings from an internal light meter.[11]

    As the aperture is adjusted, the opening expands and contracts in increments called f-stops.[a][11] The smaller the f-stop, the more light is allowed to enter the lens, increasing the exposure. Typically, f-stops range from f/1.4 to f/32[b] in standard increments: 1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, and 32.[15] The light entering the camera is halved with each increasing increment.[14]

    An image of flowers, with one in focus. The background is out of focus.
    The distance range in which objects appear clear and sharp, called depth of field, can be adjusted by many cameras. This allows a photographer to control which objects appear in focus, and which do not.

    The wider opening at lower f-stops narrows the range of focus so the background is blurry while the foreground is in focus. This depth of field increases as the aperture closes. A narrow aperture results in a high depth of field, meaning that objects at many different distances from the camera will appear to be in focus.[16] What is acceptably in focus is determined by the circle of confusion, the photographic technique, the equipment in use and the degree of magnification expected of the final image.[17]

    Shutter

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    Main article: Shutter (photography)

    The shutter, along with the aperture, is one of two ways to control the amount of light entering the camera. The shutter determines the duration that the light-sensitive surface is exposed to light. The shutter opens, light enters the camera and exposes the film or sensor to light, and then the shutter closes.[14][18]

    There are two types of mechanical shutters: the leaf-type shutter and the focal-plane shutter. The leaf-type uses a circular iris diaphragm maintained under spring tension inside or just behind the lens that rapidly opens and closes when the shutter is released.[15]

    A focal-plane shutter. In this shutter, the metal shutter blades travel vertically.

    More commonly, a focal-plane shutter is used.[14] This shutter operates close to the film plane and employs metal plates or cloth curtains with an opening that passes across the light-sensitive surface. The curtains or plates have an opening that is pulled across the film plane during exposure. The focal-plane shutter is typically used in single-lens reflex (SLR) cameras, since covering the film (rather than blocking the light passing through the lens) allows the photographer to view the image through the lens at all times, except during the exposure itself. Covering the film also facilitates removing the lens from a loaded camera, as many SLRs have interchangeable lenses.[11][15]

    digital camera may use a mechanical or electronic shutter, the latter of which is common in smartphone cameras. Electronic shutters either record data from the entire sensor simultaneously (a global shutter) or record the data line by line across the sensor (a rolling shutter).[11] In movie cameras, a rotary shutter opens and closes in sync with the advancement of each frame of film.[11][19]

    The duration for which the shutter is open is called the shutter speed or exposure time. Typical exposure times can range from one second to 1/1,000 of a second, though longer and shorter durations are not uncommon. In the early stages of photography, exposures were often several minutes long. These long exposure times often resulted in blurry images, as a single object is recorded in multiple places across a single image for the duration of the exposure. To prevent this, shorter exposure times can be used. Very short exposure times can capture fast-moving action and eliminate motion blur.[20][15][11][14] However, shorter exposure times require more light to produce a properly exposed image, so shortening the exposure time is not always possible.

    Like aperture settings, exposure times increment in powers of two. The two settings determine the exposure value (EV), a measure of how much light is recorded during the exposure. There is a direct relationship between the exposure times and aperture settings so that if the exposure time is lengthened one step, but the aperture opening is also narrowed one step, then the amount of light that contacts the film or sensor is the same.[14]

    Light meter

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    Main article: Light meter

    A handheld digital light meter showing an exposure of 1/200th at an aperture of f/11, at ISO 100. The light sensor is on top, under the white diffusing hemisphere.

    In most modern cameras, the amount of light entering the camera is measured using a built-in light meter or exposure meter.[c] Taken through the lens (called TTL metering), these readings are taken using a panel of light-sensitive semiconductors.[12] They are used to calculate optimal exposure settings. These settings are typically determined automatically as the reading is used by the camera’s microprocessor. The reading from the light meter is incorporated with aperture settings, exposure times, and film or sensor sensitivity to calculate the optimal exposure.[d]

    Light meters typically average the light in a scene to 18% middle gray. More advanced cameras are more nuanced in their metering—weighing the center of the frame more heavily (center-weighted metering), considering the differences in light across the image (matrix metering), or allowing the photographer to take a light reading at a specific point within the image (spot metering).[16][20][21][11]

    Lens

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    Main articles: Camera lens and Photographic lens design

    A camera lens is an assembly of multiple optical elements, typically made from high-quality glass.[22] Its primary function is to focus light onto a camera’s film or digital sensor, thereby producing an image.[12] This process significantly influences image quality, the overall appearance of the photo, and which parts of the scene are brought into focus.[22]

    A camera lens is constructed from a series of lens elements, small pieces of glass arranged to form an image accurately on the light-sensitive surface. Each element is designed to reduce optical aberrations, or distortions, such as chromatic aberration (a failure of the lens to focus all colors at the same point), vignetting (darkening of image corners), and distortion (bending or warping of the image). The degree of these distortions can vary depending on the subject of the photo.[22]

    The focal length of the lens, measured in millimeters, plays a critical role as it determines how much of the scene the camera can capture and how large the objects appear. Wide-angle lenses provide a broad view of the scene, while telephoto lenses capture a narrower view but magnify the objects. The focal length also influences the ease of taking clear pictures handheld, with longer lengths making it more challenging to avoid blur from small camera movements.[22]

    Two primary types of lenses include zoom and prime lenses. A zoom lens allows for changing its focal length within a certain range, providing the convenience of adjusting the scene capture without moving the camera or changing the lens. A prime lens, in contrast, has a fixed focal length. While less flexible, prime lenses often provide superior image quality, are typically lighter, and perform better in low light.[22]

    Focus involves adjusting the lens elements to sharpen the image of the subject at various distances.[23] The focus is adjusted through the focus ring on the lens, which moves the lens elements closer or further from the sensor. Autofocus is a feature included in many lenses, which uses a motor within the lens to adjust the focus quickly and precisely based on the lens’s detection of contrast or phase differences. This feature can be enabled or disabled using switches on the lens body.[12]

    Advanced lenses may include mechanical image stabilization systems that move lens elements or the image sensor itself to counteract camera shake, especially beneficial in low-light conditions or at slow shutter speeds.[22] Lens hoods, filters, and caps are accessories used alongside a lens to enhance image quality, protect the lens, or achieve specific effects.[12]

    Viewfinder

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    The camera’s viewfinder provides a real-time approximation of what will be captured by the sensor or film. It assists photographers in aligning, focusing, and adjusting the composition, lighting, and exposure of their shots, enhancing the accuracy of the final image.[14]

    Viewfinders fall into two primary categories: optical and electronic. Optical viewfinders, commonly found in Single-Lens Reflex (SLR) cameras, use a system of mirrors or prisms to reflect light from the lens to the viewfinder, providing a clear, real-time view of the scene. Electronic viewfinders, typical in mirrorless cameras, project an electronic image onto a small display, offering a wider range of information such as live exposure previews and histograms, albeit at the cost of potential lag and higher battery consumption.[11] Specialized viewfinder systems exist for specific applications, like subminiature cameras for spying or underwater photography.[18]

    Parallax error, resulting from misalignment between the viewfinder and lens axes, can cause inaccurate representations of the subject’s position. While negligible with distant subjects, this error becomes prominent with closer ones. Some viewfinders incorporate parallax-compensating devices to mitigate that issue.[15]

    Film and sensor

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    Image capture in a camera occurs when light strikes a light-sensitive surface: photographic film or a digital sensor.[18] Housed within the camera body, the film or sensor records the light’s pattern when the shutter is briefly opened to allow light to pass during the exposure.[16]

    Loading film into a film camera is a manual process. The film, typically housed in a cartridge, is loaded into a designated slot in the camera. One end of the film strip, the film leader, is manually threaded onto a take-up spool. Once the back of the camera is closed, the film advance lever or knob is used to ensure the film is correctly placed. The photographer then winds the film, either manually or automatically depending on the camera, to position a blank portion of the film in the path of the light. Each time a photo is taken, the film advance mechanism moves the exposed film out of the way, bringing a new, unexposed section of film into position for the next shot.[16]

    The film must be advanced after each shot to prevent double exposure — where the same section of film is exposed to light twice, resulting in overlapped images. Once all frames on the film roll have been exposed, the film is rewound back into the cartridge, ready to be removed from the camera for developing.[18]

    In digital cameras, sensors typically comprise Charge-Coupled Devices (CCDs) or Complementary Metal-Oxide-Semiconductor (CMOS) chips, both of which convert incoming light into electrical charges to form digital images.[11] CCD sensors, though power-intensive, are recognized for their excellent light sensitivity and image quality. Conversely, CMOS sensors offer individual pixel readouts, leading to less power consumption and faster frame rates, with their image quality having improved significantly over time.

    Digital cameras convert light into electronic data that can be directly processed and stored. The volume of data generated is dictated by the sensor’s size and properties, necessitating storage media such as Compact FlashMemory Sticks, and SD (Secure Digital) cards.[18] Modern digital cameras typically feature a built-in monitor for immediate image review and adjustments.[11] Digital images are also more readily handled and manipulated by computers, offering a significant advantage in terms of flexibility and post-processing potential over traditional film.[18]

    Camera accessories

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    Flash

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    flash provides a short burst of bright light during exposure and is a commonly used artificial light source in photography. Most modern flash systems use a battery-powered high-voltage discharge through a gas-filled tube to generate bright light for a very short time (1/1,000 of a second or less).[e][21]

    Many flash units measure the light reflected from the flash to help determine the appropriate duration of the flash. When the flash is attached directly to the camera—typically in a slot at the top of the camera (the flash shoe or hot shoe) or through a cable—activating the shutter on the camera triggers the flash, and the camera’s internal light meter can help determine the duration of the flash.[21][16]

    Additional flash equipment can include a light diffuser, mount and stand, reflector, soft box, trigger and cord.

    Other accessories

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    Accessories for cameras are mainly used for care, protection, special effects, and functions.

    • Lens hood: used on the end of a lens to block the sun or other light source to prevent glare and lens flare (see also matte box).
    • Lens cap: covers and protects the camera lens when not in use.
    • Lens adapter: allows the use of lenses other than those for which the camera was designed.
    • Filter: allows artificial colors or changes light density.
    • Lens extension tube: allows close focus in macro photography.
    • Care and protection: including camera case and cover, maintenance tools, and screen protector.
    • Camera monitor: provides an off-camera view of the composition with a brighter and more colorful screen, and typically exposes more advanced tools such as framing guides, focus peakingzebra stripeswaveform monitors (oftentimes as an “RGB parade”), vectorscopes and false color to highlight areas of the image critical to the photographer.
    • Tripod: primarily used for keeping the camera steady while recording video, doing a long exposure, and time-lapse photography.
    • Microscope adapter: used to connect a camera to a microscope to photograph what the microscope is examining.
    • Cable release: used to remotely control the shutter using a remote shutter button that can be connected to the camera via a cable. It can be used to lock the shutter open for the desired period, and it is also commonly used to prevent the camera shake from pressing the built-in camera shutter button.
    • Dew shield: prevents moisture build-up on the lens.
    • UV filter: can protect the front element of a lens from scratches, cracks, smudges, dirt, dust, and moisture while keeping a minimum impact on image quality.
    • Battery and sometimes a charger.

    Large format cameras use special equipment that includes a magnifier loupe, view finder, angle finder, and focusing rail/truck. Some professional SLRs can be provided with interchangeable finders for eye-level or waist-level focusing, focusing screens, eyecup, data backs, motor-drives for film transportation or external battery packs.

    Primary types

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    Single-lens reflex (SLR) camera

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    Main article: Single-lens reflex camera

    Further information: Instant return mirror

    Nikon D200 digital camera

    In photography, the single-lens reflex camera (SLR) is provided with a mirror to redirect light from the lens to the viewfinder prior to releasing the shutter for composing and focusing an image. When the shutter is released, the mirror swings up and away, allowing the exposure of the photographic medium, and instantly returns after the exposure is finished. No SLR camera before 1954 had this feature, although the mirror on some early SLR cameras was entirely operated by the force exerted on the shutter release and only returned when the finger pressure was released.[24][25] The Asahiflex II, released by Japanese company Asahi (Pentax) in 1954, was the world’s first SLR camera with an instant return mirror.[26]

    In the single-lens reflex camera, the photographer sees the scene through the camera lens. This avoids the problem of parallax which occurs when the viewfinder or viewing lens is separated from the taking lens. Single-lens reflex cameras have been made in several formats including sheet film 5×7″ and 4×5″, roll film 220/120 taking 8,10, 12, or 16 photographs on a 120 roll, and twice that number of a 220 film. These correspond to 6×9, 6×7, 6×6, and 6×4.5 respectively (all dimensions in cm). Notable manufacturers of large format and roll film SLR cameras include BronicaGraflexHasselbladSeagullMamiya and Pentax. However, the most common format of SLR cameras has been 35 mm and subsequently the migration to digital SLR cameras, using almost identical sized bodies and sometimes using the same lens systems.

    Almost all SLR cameras use a front-surfaced mirror in the optical path to direct the light from the lens via a viewing screen and pentaprism to the eyepiece. At the time of exposure, the mirror is flipped up out of the light path before the shutter opens. Some early cameras experimented with other methods of providing through-the-lens viewing, including the use of a semi-transparent pellicle as in the Canon Pellix[27] and others with a small periscope such as in the Corfield Periflex series.[28]

    Large-format camera

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    Main article: View camera

    The large-format camera, taking sheet film, is a direct successor of the early plate cameras and remained in use for high-quality photography and technical, architectural, and industrial photography. There are three common types: the view camera, with its monorail and field camera variants, and the press camera. They have extensible bellows with the lens and shutter mounted on a lens plate at the front. Backs taking roll film and later digital backs are available in addition to the standard dark slide back. These cameras have a wide range of movements allowing very close control of focus and perspective. Composition and focusing are done on view cameras by viewing a ground-glass screen which is replaced by the film to make the exposure; they are suitable for static subjects only and are slow to use.

    Plate camera

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    19th-century studio camera with bellows for focusing

    Main article: Photographic plate

    The earliest cameras produced in significant numbers were plate cameras, using sensitized glass plates. Light entered a lens mounted on a lens board which was separated from the plate by extendible bellows. There were simple box cameras for glass plates but also single-lens reflex cameras with interchangeable lenses and even for color photography (Autochrome Lumière). Many of these cameras had controls to raise, lower, and tilt the lens forwards or backward to control perspective.

    Focusing of these plate cameras was by the use of a ground glass screen at the point of focus. Because lens design only allowed rather small aperture lenses, the image on the ground glass screen was faint and most photographers had a dark cloth to cover their heads to allow focusing and composition to be carried out more quickly. When focus and composition were satisfactory, the ground glass screen was removed, and a sensitized plate was put in its place protected by a dark slide. To make the exposure, the dark decline was carefully slid out and the shutter opened, and then closed and the dark fall replaced.

    Glass plates were later replaced by sheet film in a dark slide for sheet film; adapter sleeves were made to allow sheet film to be used in plate holders. In addition to the ground glass, a simple optical viewfinder was often fitted.

    Medium-format camera

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    Main article: Medium format

    Hasselblad medium format camera

    Medium-format cameras have a film size between the large-format cameras and smaller 35 mm cameras.[29] Typically these systems use 120 or 220 roll film.[30] The most common image sizes are 6×4.5 cm, 6×6 cm and 6×7 cm; the older 6×9 cm is rarely used. The designs of this kind of camera show greater variation than their larger brethren, ranging from monorail systems through the classic Hasselblad model with separate backs, to smaller rangefinder cameras. There are even compact amateur cameras available in this format.

    Twin-lens reflex camera

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    Main article: Twin-lens reflex camera

    Twin-lens reflex camera

    Twin-lens reflex cameras used a pair of nearly identical lenses: one to form the image and one as a viewfinder.[31] The lenses were arranged with the viewing lens immediately above the taking lens. The viewing lens projects an image onto a viewing screen which can be seen from above. Some manufacturers such as Mamiya also provided a reflex head to attach to the viewing screen to allow the camera to be held to the eye when in use. The advantage of a TLR was that it could be easily focused using the viewing screen and that under most circumstances the view seen on the viewing screen was identical to that recorded on film. At close distances, however, parallax errors were encountered, and some cameras also included an indicator to show what part of the composition would be excluded.

    Some TLRs had interchangeable lenses, but as these had to be paired lenses, they were relatively heavy and did not provide the range of focal lengths that the SLR could support. Most TLRs used 120 or 220 films; some used the smaller 127 films.

    Compact cameras

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    Instant camera

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    Main article: Instant camera

    Instant Camera

    After exposure, every photograph is taken through pinch rollers inside the instant camera. Thereby the developer paste contained in the paper ‘sandwich’ is distributed on the image. After a minute, the cover sheet just needs to be removed and one gets a single original positive image with a fixed format. With some systems, it was also possible to create an instant image negative, from which then could be made copies in the photo lab. The ultimate development was the SX-70 system of Polaroid, in which a row of ten shots – engine driven – could be made without having to remove any cover sheets from the picture. There were instant cameras for a variety of formats, as well as adapters for instant film use in medium- and large-format cameras.

    Subminiature camera

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    Main article: Subminiature camera

    Subminiature spy camera

    Subminiature cameras were first produced in the twentieth century and use film significantly smaller than 35mm. The expensive 8×11mm Minox, the only type of camera produced by the company from 1937 to 1976, became very widely known and was often used for espionage (the Minox company later also produced larger cameras). Later inexpensive subminiatures were made for general use, some using rewound 16 mm cine film. Image quality with these small film sizes was limited.

    Folding camera

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    Main article: Folding camera

    Folding camera

    The introduction of films enabled the existing designs for plate cameras to be made much smaller and for the baseplate to be hinged so that it could be folded up, compressing the bellows. These designs were very compact and small models were dubbed vest pocket cameras. One of the smallest and best-selling cameras was the Vest Pocket Kodak, sold in two generations between 1912 and 1934. Folding roll film cameras were preceded by folding plate cameras, more compact than other designs.

    Box camera

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    Main article: Box camera

    Kodak box camera

    Box cameras were introduced as budget-level cameras and had few if any controls. The original box Brownie models had a small reflex viewfinder mounted on the top of the camera and had no aperture or focusing controls and just a simple shutter. Later models such as the Brownie 127 had larger direct view optical viewfinders together with a curved film path to reduce the impact of deficiencies in the lens.

    Rangefinder camera

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    Main article: Rangefinder camera

    Rangefinder camera, Leica c. 1936

    As camera lens technology developed and wide aperture lenses became more common, rangefinder cameras were introduced to make focusing more precise. Early rangefinders had two separate viewfinder windows, one of which is linked to the focusing mechanisms and moved right or left as the focusing ring is turned. The two separate images are brought together on a ground glass viewing screen. When vertical lines in the object being photographed meet exactly in the combined image, the object is in focus. A normal composition viewfinder is also provided. Later the viewfinder and rangefinder were combined. Many rangefinder cameras had interchangeable lenses, each lens requiring its range- and viewfinder linkages.

    Rangefinder cameras were produced in half- and full-frame 35 mm and roll film (medium format).

    Motion picture cameras

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    Main article: Movie camera

    Further information: Digital movie camera

    movie camera or a video camera operates similarly to a still camera, except it records a series of static images in rapid succession, commonly at a rate of 24 frames per second. When the images are combined and displayed in order, the illusion of motion is achieved.[32]: 4 

    Cameras that capture many images in sequence are known as movie cameras or as cine cameras in Europe; those designed for single images are still cameras. However, these categories overlap as still cameras are often used to capture moving images in special effects work and many modern cameras can quickly switch between still and motion recording modes.

    A ciné camera or movie camera takes a rapid sequence of photographs on an image sensor or strips of film. In contrast to a still camera, which captures a single snapshot at a time, the ciné camera takes a series of images, each called a frame, through the use of an intermittent mechanism.

    The frames are later played back in a ciné projector at a specific speed, called the frame rate (number of frames per second). While viewing, a person’s visual system merges the separate pictures to create the illusion of motion. The first ciné camera was built around 1888 and by 1890 several types were being manufactured. The standard film size for ciné cameras was quickly established as 35mm film and this remained in use until the transition to digital cinematography. Other professional standard formats include 70 mm film and 16 mm film whilst amateur filmmakers used 9.5 mm film, 8 mm film, or Standard 8 and Super 8 before the move into digital format.

    The size and complexity of ciné cameras vary greatly depending on the uses required of the camera. Some professional equipment is very large and too heavy to be handheld whilst some amateur cameras were designed to be very small and light for single-handed operation.

    Professional video camera

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    Arri Alexa, a digital movie camera

    Main article: Professional video camera

    Further information: Video camera

    professional video camera (often called a television camera even though the use has spread beyond television) is a high-end device for creating electronic moving images (as opposed to a movie camera, that earlier recorded the images on film). Originally developed for use in television studios, they are now also used for music videos, direct-to-video movies, corporate and educational videos, marriage videos, etc.

    These cameras earlier used vacuum tubes and later electronic image sensors.

    Camcorders

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    A Sony HDV Camcorder
    Sony HDR-HC1E, a HDV camcorder.

    Main article: Camcorder

    A camcorder is an electronic device combining a video camera and a video recorder. Although marketing materials may use the colloquial term “camcorder”, the name on the package and manual is often “video camera recorder”. Most devices capable of recording video are camera phones and digital cameras primarily intended for still pictures; the term “camcorder” is used to describe a portable, self-contained device, with video capture and recording its primary function.

    Digital camera

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    Main article: Digital camera

    Disassembled digital camera

    Further information: Digital imageDigital imagingDigital photographyDigital single-lens reflex camera, and Digital video

    A digital camera (or digicam) is a camera that encodes digital images and videos and stores them for later reproduction.[33] They typically use semiconductor image sensors.[34] Most cameras sold today are digital,[35] and they are incorporated into many devices ranging from mobile phones (called camera phones) to vehicles.

    Digital and film cameras share an optical system, typically using a lens of variable aperture to focus light onto an image pickup device.[36] The aperture and shutter admit the correct amount of light to the imager, just as with film but the image pickup device is electronic rather than chemical. However, unlike film cameras, digital cameras can display images on a screen immediately after being captured or recorded, and store and delete images from memory. Most digital cameras can also record moving videos with sound. Some digital cameras can crop and stitch pictures & perform other elementary image editing.

    Consumers adopted digital cameras in the 1990s. Professional video cameras transitioned to digital around the 2000s–2010s. Finally, movie cameras transitioned to digital in the 2010s.

    The first camera using digital electronics to capture and store images was developed by Kodak engineer Steven Sasson in 1975. He used a charge-coupled device (CCD) provided by Fairchild Semiconductor, which provided only 0.01 megapixels to capture images. Sasson combined the CCD device with movie camera parts to create a digital camera that saved black and white images onto a cassette tape.[37]: 442 The images were then read from the cassette and viewed on a TV monitor.[38]: 225  Later, cassette tapes were replaced by flash memory.

    In 1986, Japanese company Nikon introduced an analog-recording electronic single-lens reflex camera, the Nikon SVC.[39]

    Sony Alpha 1, a full-frame mirrorless digital camera

    The first full-frame digital SLR cameras were developed in Japan from around 2000 to 2002: the MZ-D by Pentax,[40] the N Digital by Contax‘s Japanese R6D team,[41] and the EOS-1Ds by Canon.[42] Gradually in the 2000s, the full-frame DSLR became the dominant camera type for professional photography.[citation needed]

    On most digital cameras a display, often a liquid crystal display (LCD), permits the user to view the scene to be recorded and settings such as ISO speed, exposure, and shutter speed.[10]: 6–7 [43]: 12 

    Camera phone

    [edit]

    Smartphone with built-in camera

    Main article: Camera phone

    Further information: Front-facing camera and Selfie

    In 2000, Sharp introduced the world’s first digital camera phone, the J-SH04 J-Phone, in Japan.[44] By the mid-2000s, higher-end cell phones had an integrated digital camera, and by the beginning of the 2010s, almost all smartphones had an integrated digital camera.

  • Motorcycle

    motorcycle (motorbikebike, or, if three-wheeled, a trike) is a two or three-wheeled motor vehicle steered by a handlebar from a saddle-style seat.[1][2][3]

    Motorcycle designs vary greatly to suit a range of different purposes: long-distance travel, commutingcruisingsport (including racing), and off-road riding. Motorcycling is riding a motorcycle and being involved in other related social activities such as joining a motorcycle club and attending motorcycle rallies.

    The 1885 Daimler Reitwagen made by Gottlieb Daimler and Wilhelm Maybach in Germany was the first internal combustion, petroleum-fueled motorcycle. In 1894, Hildebrand & Wolfmüller became the first series production motorcycle.[4][5]

    Globally, motorcycles are comparable numerically to cars as a method of transport: in 2021, approximately 58.6 million new motorcycles were sold around the world,[6] while 66.7 million cars were sold over the same period.[7]

    In 2022, the top four motorcycle producers by volume and type were HondaYamahaKawasaki, and Suzuki.[8]

    According to the US Department of Transportation, the number of fatalities per vehicle mile traveled was 37 times higher for motorcycles than for cars.[9]

    Types

    [edit]

    Main article: Types of motorcycles

    The term motorcycle has different legal definitions depending on jurisdiction (see § Legal definitions and restrictions).

    There are three major types of motorcycle: street, off-road, and dual purpose. Within these types, there are many sub-types of motorcycles for different purposes. There is often a racing counterpart to each type, such as road racing and street bikes, or motocross including dirt bikes.

    Street bikes include cruiserssportbikesscooters and mopeds, and many other types. Off-road motorcycles include many types designed for dirt-oriented racing classes such as motocross and are not street legal in most areas. Dual purpose machines like the dual-sport style are made to go off-road but include features to make them legal and comfortable on the street as well.

    Each configuration offers either specialised advantage or broad capability, and each design creates a different riding posture.

    In some countries the use of pillions (rear seats) is restricted.

    History

    [edit]

    Main article: History of the motorcycle

    Experimentation and invention

    [edit]

    Replica of the Daimler-Maybach Reitwagen

    The first internal combustionpetroleum fueled motorcycle was the Daimler Reitwagen. It was designed and built by the German inventors Gottlieb Daimler and Wilhelm Maybach in Bad Cannstatt, Germany, in 1885.[10] This vehicle was unlike either the safety bicycles or the boneshaker bicycles of the era in that it had zero degrees of steering axis angle and no fork offset, and thus did not use the principles of bicycle and motorcycle dynamics developed nearly 70 years earlier. Instead, it relied on two outrigger wheels to remain upright while turning.[11]

    The inventors called their invention the Reitwagen (“riding car”). It was designed as an expedient testbed for their new engine, rather than a true prototype vehicle.[12][13]

    Butler’s Patent Velocycle

    The first commercial design for a self-propelled cycle was a three-wheel design called the Butler Petrol Cycle, conceived of Edward Butler in England in 1884.[14] He exhibited his plans for the vehicle at the Stanley Cycle Show in London in 1884. The vehicle was built by the Merryweather Fire Engine company in Greenwich, in 1888.[15]

    The Butler Petrol Cycle was a three-wheeled vehicle, with the rear wheel directly driven by a 58 hp (0.47 kW), 40 cc (2.4 cu in) displacement, 2+14 in × 5 in (57 mm × 127 mm) bore × stroke, flat twin four-stroke engine (with magneto ignition replaced by coil and battery) equipped with rotary valves and a float-fed carburettor (five years before Maybach) and Ackermann steering, all of which were state of the art at the time. Starting was by compressed air. The engine was liquid-cooled, with a radiator over the rear driving wheel. Speed was controlled by means of a throttle valve lever. No braking system was fitted; the vehicle was stopped by raising and lowering the rear driving wheel using a foot-operated lever; the weight of the machine was then borne by two small castor wheels. The driver was seated between the front wheels. It was not, however, a success, as Butler failed to find sufficient financial backing.[16]

    Many authorities have excluded steam poweredelectric motorcycles or diesel-powered two-wheelers from the definition of a ‘motorcycle’, and credit the Daimler Reitwagen as the world’s first motorcycle.[17][18][19] Given the rapid rise in use of electric motorcycles worldwide,[20] defining only internal-combustion powered two-wheelers as ‘motorcycles’ is increasingly problematic. The first (petroleum fueled) internal-combustion motorcycles, like the German Reitwagen, were, however, also the first practical motorcycles.[18][21][22]

    If a two-wheeled vehicle with steam propulsion is considered a motorcycle, then the first motorcycles built seem to be the French Michaux-Perreaux steam velocipede which patent application was filed in December 1868,[12][13] constructed around the same time as the American Roper steam velocipede, built by Sylvester H. Roper of Roxbury, Massachusetts,[12][13] who had been demonstrating his machine at fairs and circuses in the eastern U.S. since 1867.[10] Roper built about 10 steam cars and cycles from the 1860s until his death in 1896.[19]

    Summary of early inventions

    [edit]

    YearVehicleNumber of wheelsInventorEngine typeNotes
    1867–1868Michaux-Perreaux steam velocipede2Pierre Michaux
    Louis-Guillaume Perreaux
    SteamOne made
    1867–1868Roper steam velocipede2Sylvester RoperSteamOne made
    1885Daimler Reitwagen2 (plus 2 outriggers)Gottlieb Daimler
    Wilhelm Maybach
    Petroleum internal-combustionOne made
    1887Butler Petrol Cycle3 (plus 2 castors)Edward ButlerPetroleum internal-combustion
    1894Hildebrand & Wolfmüller2Heinrich Hildebrand
    Wilhelm Hildebrand
    Alois Wolfmüller
    Petroleum internal-combustionModern configurationFirst mass-produced motorcycleFirst machine to be called “motorcycle”

    First motorcycle companies

    [edit]

    Diagram of 1894 Hildebrand & Wolfmüller

    In 1894, Hildebrand & Wolfmüller became the first series production motorcycle, and the first to be called a motorcycle (GermanMotorrad).[12][13][19][23] Excelsior Motor Company, originally a bicycle manufacturing company based in Coventry, England, began production of their first motorcycle model in 1896.

    The first production motorcycle in the US was the Orient-Aster, built by Charles Metz in 1898 at his factory in Waltham, Massachusetts.

    In the early period of motorcycle history, many producers of bicycles adapted their designs to accommodate the new internal combustion engine. As the engines became more powerful and designs outgrew the bicycle origins, the number of motorcycle producers increased. Many of the nineteenth-century inventors who worked on early motorcycles often moved on to other inventions. Daimler and Roper, for example, both went on to develop automobiles.

    1902 Orient motocycle

    At the end of the 19th century the first major mass-production firms were set up. In 1898, Triumph Motorcycles in England began producing motorbikes, and by 1903 it was producing over 500 bikes. Other British firms were Royal EnfieldNortonDouglas Motorcycles and Birmingham Small Arms Company who began motorbike production in 1899, 1902, 1907 and 1910, respectively.[24] Indian began production in 1901 and Harley-Davidson was established two years later. By the outbreak of World War I, the largest motorcycle manufacturer in the world was Indian,[25][26] producing over 20,000 bikes per year.[27]

    First World War

    [edit]

    During the First World War, motorbike production was greatly ramped up for the war effort to supply effective communications with front line troops. Messengers on horses were replaced with despatch riders on motorcycles carrying messages, performing reconnaissance and acting as a military police. American company Harley-Davidson was devoting over 50% of its factory output toward military contract by the end of the war. The British company Triumph Motorcycles sold more than 30,000 of its Triumph Type H model to allied forces during the war. With the rear wheel driven by a belt, the Model H was fitted with a 499 cc (30.5 cu in) air-cooled four-stroke single-cylinder engine. It was also the first Triumph without pedals.[28][better source needed]

    The Model H in particular, is regarded by many as having been the first “modern motorcycle”.[29] Introduced in 1915 it had a 550 cc side-valve four-stroke engine with a three-speed gearbox and belt transmission. It was so popular with its users that it was nicknamed the “Trusty Triumph”.[30]

    Postwar

    [edit]

    Motorcycle rider on his Rudge-Whitworth motorbike, Australia, c. 1935

    By 1920, Harley-Davidson was the largest manufacturer,[31] with their motorcycles being sold by dealers in 67 countries.[32][33]

    Amongst many British motorcycle manufacturers, Chater-Lea with its twin-cylinder models followed by its large singles in the 1920s stood out. Initially, using converted a Woodmann-designed OHV Blackburne engine it became the first 350 cc to exceed 100 mph (160 km/h), recording 100.81 mph (162.24 km/h) over the flying kilometre during April 1924.[7] Later, Chater-Lea set a world record for the flying kilometre for 350 cc and 500 cc motorcycles at 102.9 mph (165.6 km/h) for the firm. Chater-Lea produced variants of these world-beating sports models and became popular among racers at the Isle of Man TT. Today, the firm is probably best remembered for its long-term contract to manufacture and supply AA Patrol motorcycles and sidecars.[citation needed]

    By the late 1920s or early 1930s, DKW in Germany took over as the largest manufacturer.[34][35][36]

    NSU Sportmax streamlined motorcycle, 250 cc class winner of the 1955 Grand Prix season

    In the 1950s, streamlining began to play an increasing part in the development of racing motorcycles and the “dustbin fairing” held out the possibility of radical changes to motorcycle design. NSU and Moto Guzzi were in the vanguard of this development, both producing very radical designs well ahead of their time.[37] NSU produced the most advanced design, but after the deaths of four NSU riders in the 1954–1956 seasons, they abandoned further development and quit Grand Prix motorcycle racing.[38]

    Moto Guzzi produced competitive race machines, and until the end of 1957 had a succession of victories.[39] The following year, 1958, full enclosure fairings were banned from racing by the FIM in the light of the safety concerns.

    From the 1960s through the 1990s, small two-stroke motorcycles were popular worldwide, partly as a result of East German MZs Walter Kaaden’s engine work in the 1950s.[40]

    Today

    [edit]

    Royal Enfield Bullet

    In the 21st century, the motorcycle industry is mainly dominated by Indian and Japanese motorcycle companies. In addition to the large capacity motorcycles, there is a large market in smaller capacity (less than 300 cc) motorcycles, mostly concentrated in Asian and African countries and produced in China and India.[citation needed] A Japanese example is the 1958 Honda Super Cub, which went on to become the biggest selling vehicle of all time, with its 60 millionth unit produced in April 2008.[41] Today, this area is dominated by mostly Indian companies with Hero MotoCorp emerging as the world’s largest manufacturer of two wheelers. Its Splendor model has sold more than 8.5 million to date.[42] Other major producers are Bajaj and TVS Motors.[43]

    Yamaha Troops motorbike

    Technical aspects

    [edit]

    Suzuki GS500 with a clearly visible frame, painted silver

    Construction

    [edit]

    See also: Motorcycle components and Motorcycle design

    Motorcycle construction is the engineering, manufacturing, and assembly of components and systems for a motorcycle which results in the performance, cost, and aesthetics desired by the designer. With some exceptions, construction of modern mass-produced motorcycles has standardised on a steel or aluminium frametelescopic forks holding the front wheel, and disc brakes. Some other body parts, designed for either aesthetic or performance reasons may be added. A petrol-powered engine typically consisting of between one and four cylinders (and less commonly, up to eight cylinders) coupled to a manual five- or six-speed sequential transmission drives the swingarm-mounted rear wheel by a chaindriveshaft, or belt. The repair can be done using a motorcycle lift.

    Fuel economy

    [edit]

    Motorcycle fuel economy varies greatly with engine displacement and riding style.[44] A streamlined, fully faired Matzu Matsuzawa Honda XL125 achieved 470 mpg‑US (0.50 L/100 km; 560 mpg‑imp) in the Craig Vetter Fuel Economy Challenge “on real highways – in real conditions”.[45] Due to low engine displacements (100–200 cc (6.1–12.2 cu in)), and high power-to-mass ratios, motorcycles offer good fuel economy. Under conditions of fuel scarcity like 1950s Britain and modern developing nations, motorcycles claim large shares of the vehicle market. In the United States, the average motorcycle fuel economy is 44 miles per US gallon (19 km per liter).[46]

    Electric motorcycles

    [edit]

    Main article: Electric motorcycles and scooters

    Very high fuel economy equivalents are often derived by electric motorcycles. Electric motorcycles are nearly silent, zero-emission electric motor-driven vehicles. Operating range and top speed are limited by battery technology.[47] Fuel cells and petroleum-electric hybrids are also under development to extend the range and improve performance of the electric drive system.

    Reliability

    [edit]

    A 2013 survey of 4,424 readers of the US Consumer Reports magazine collected reliability data on 4,680 motorcycles purchased new from 2009 to 2012.[48] The most common problem areas were accessoriesbrakes, electrical (including starterschargingignition), and fuel systems, and the types of motorcycles with the greatest problems were touring, off-road/dual sport, sport-touring, and cruisers.[48] There were not enough sport bikes in the survey for a statistically significant conclusion, though the data hinted at reliability as good as cruisers.[48] These results may be partially explained by accessories including such equipment as fairings, luggage, and auxiliary lighting, which are frequently added to touring, adventure touring/dual sport and sport touring bikes.[49] Trouble with fuel systems is often the result of improper winter storage, and brake problems may also be due to poor maintenance.[48] Of the five brands with enough data to draw conclusions, Honda, Kawasaki and Yamaha were statistically tied, with 11 to 14% of those bikes in the survey experiencing major repairs.[48] Harley-Davidsons had a rate of 24%, while BMWs did worse, with 30% of those needing major repairs.[48] There were not enough Triumph and Suzuki motorcycles surveyed for a statistically sound conclusion, though it appeared Suzukis were as reliable as the other three Japanese brands while Triumphs were comparable to Harley-Davidson and BMW.[48] Three-fourths of the repairs in the survey cost less than US$200 and two-thirds of the motorcycles were repaired in less than two days.[48] In spite of their relatively worse reliability in this survey, Harley-Davidson and BMW owners showed the greatest owner satisfaction, and three-fourths of them said they would buy the same bike again, followed by 72% of Honda owners and 60 to 63% of Kawasaki and Yamaha owners.[48]

    Dynamics

    [edit]

    Racing motorcycles leaning in a turn

    Main article: Bicycle and motorcycle dynamics

    Two-wheeled motorcycles stay upright while rolling due to a physical property known as conservation of angular momentum in the wheels. Angular momentum points along the axle, and it “wants” to stay pointing in that direction.

    Different types of motorcycles have different dynamics and these play a role in how a motorcycle performs in given conditions. For example, one with a longer wheelbase provides the feeling of more stability by responding less to disturbances.[50] Motorcycle tyres have a large influence over handling.

    Motorcycles must be leaned in order to make turns. This lean is induced by the method known as countersteering, in which the rider momentarily steers the handlebars in the direction opposite of the desired turn. This practice is counterintuitive and therefore often confusing to novices – and even many experienced motorcyclists.[51][52][53]

    With such short wheelbase, motorcycles can generate enough torque at the rear wheel, and enough stopping force at the front wheel, to lift the opposite wheel off the road. These actions, if performed on purpose, are known as wheelies and stoppies (or endos) respectively.

    Accessories

    [edit]

    Main article: Motorcycle accessories

    Various features and accessories may be attached to a motorcycle either as OEM (factory-fitted) or aftermarket. Such accessories are selected by the owner to enhance the motorcycle’s appearance, safety, performance, or comfort, and may include anything from mobile electronics to sidecars and trailers.

    Records

    [edit]

    Safety

    [edit]

    Motorcycle equipment

    Main articles: Motorcycle safety and Motorcycle safety clothing

    Wearing a motorcycle helmet (which is a legal requirement in many countries) reduces the risks of death or head injury in a motorcycle crash.

    Motorcycles have a higher rate of fatal accidents than automobiles or trucks and buses. United States Department of Transportation data for 2005 from the Fatality Analysis Reporting System show that for passenger cars, 18.62 fatal crashes occur per 100,000 registered vehicles. For motorcycles this figure is higher at 75.19 per 100,000 registered vehicles – four times higher than for cars.[56] The same data shows that 1.56 fatalities occur per 100 million vehicle miles travelled for passenger cars, whereas for motorcycles the figure is 43.47 which is 28 times higher than for cars (37 times more deaths per mile travelled in 2007).[9] Furthermore, for motorcycles the accident rates have increased significantly since the end of the 1990s, while the rates have dropped for passenger cars.

    The most common configuration of motorcycle accidents in the United States is when a motorist pulls out or turns in front of a motorcyclist, violating their right-of-way.[57] This is sometimes called a SMIDSY, an acronym formed from the motorists’ common response of “Sorry mate, I didn’t see you”.[58] Motorcyclists can anticipate and avoid some of these crashes with proper training, increasing their visibility to other traffic, keeping to the speed limits, and not consuming alcohol or other drugs before riding.[59]

    The United Kingdom has several organisations dedicated to improving motorcycle safety by providing advanced rider training beyond what is necessary to pass the basic motorcycle licence test. These include the Institute of Advanced Motorists (IAM) and the Royal Society for the Prevention of Accidents (RoSPA). Along with increased personal safety, riders with these advanced qualifications may benefit from reduced insurance costs.[60]

    In South Africa, the Think Bike campaign is dedicated to increasing both motorcycle safety and the awareness of motorcycles on the country’s roads. The campaign, while strongest in the Gauteng province, has representation in Western Cape, KwaZulu Natal and the Free State. It has dozens of trained marshals available for various events such as cycle races and is deeply involved in numerous other projects such as the annual Motorcycle Toy Run.[61]

    Motorcycle safety education is offered throughout the United States by organisations ranging from state agencies to non-profit organisations to corporations. Most states use the courses designed by the Motorcycle Safety Foundation (MSF), while Oregon and Idaho developed their own. All of the training programs include a Basic Rider Course, an Intermediate Rider Course and an Advanced Rider Course.

    An MSF rider course for novices

    In Ireland, since 2010,[62] in the UK and some Australian jurisdictions, such as VictoriaNew South Wales,[63] the Australian Capital Territory,[64] Tasmania[65] and the Northern Territory,[66] it is compulsory to complete a basic rider training course before being issued a Learners Licence, after which they can ride on public roads.

    In Canada, motorcycle rider training is compulsory in Quebec and Manitoba only, but all provinces and territories have graduated licence programs which place restrictions on new drivers until they have gained experience. Eligibility for a full motorcycle licence or endorsement for completing a Motorcycle Safety course varies by province. Without the Motorcycle Safety Course the chance of getting insurance for the motorcycle is very low. The Canada Safety Council, a non-profit safety organisation, offers the Gearing Up program across Canada and is endorsed by the Motorcycle and Moped Industry Council.[67] Training course graduates may qualify for reduced insurance premiums.

    Motorcyclists and motor scooter riders are also exposed to an increased risk of suffering hearing damage such as hearing loss and tinnitus (ringing ears).[68][69] The noise is caused by wind noise while riding, rolling noise from the tyres and the engine itself.[70] The helmet only provides insufficient protection against high sound pressure levels.[71] Medicine (as of 2024) is not able to cure hearing damage. Wearing hearing protection, such as special earplugs for motorcyclists, can help prevent hearing damage.

    Motorcycle rider postures

    [edit]

    BMW C1, with a more upright seating position
    Bombardier Can-Am Spyder, showing location of rider on the trike

    The motorcyclist’s riding position depends on rider body-geometry (anthropometry) combined with the geometry of the motorcycle itself. These factors create a set of three basic postures.[72]

    • Sport – the rider leans forward into the wind and the weight of the upper torso is supported by the rider’s core at low speed and air pressure at high speed.[73] The footpegs are below the rider or to the rear. The reduced frontal area cuts wind resistance and allows higher speeds. At low-speed in this position the rider’s arms may bear some of the weight of the rider’s torso, which can be problematic.
    • Standard – the rider sits upright or leans forward slightly. The feet are below the rider. These are motorcycles that are not specialised to one task, so they do not excel in any particular area.[74][75] The standard posture is used with touring and commuting as well as dirt and dual-sport bikes, and may offer advantages for beginners.[76]
    • Cruiser – the rider sits at a lower seat height with the upper torso upright or leaning slightly rearward. Legs are extended forwards, sometimes out of reach of the regular controls on cruiser pegs. The low seat height can be a consideration for new or short riders. Handlebars tend to be high and wide. The emphasis is on comfort while compromising cornering ability because of low ground clearance and the greater likelihood of scraping foot pegs, floor boards, or other parts if turns are taken at the speeds other motorcycles can more readily accomplish.[77][78]

    Factors of a motorcycle’s ergonomic geometry that determine the seating posture include the height, angle and location of footpegs, seat and handlebars. Factors in a rider’s physical geometry that contribute to seating posture include torso, arm, thigh and leg length, and overall rider height.

    [edit]

    Main article: Legal definition of motorcycle

    A motorcycle is broadly defined by law in most countries for the purposes of registration, taxation and rider licensing as a powered two-wheel motor vehicle. Most countries distinguish between mopeds of 49 cc and the more powerful, larger vehicles, including scooter type motorcycles.[79] Many jurisdictions include some forms of three-wheeled cars as motorcycles.

    In Nigeria, motorcycles, popularly referred to as Okada have been subject of many controversies with regards to safety and security followed by restriction of movement in many states. In 2020, it was banned in Lagos, Nigeria’s most populous city.[80][81]

    Environmental impact

    [edit]

    Motorcycles and scooters’ low fuel consumption has attracted interest in the United States from environmentalists and those affected by increased fuel prices.[82][83] Piaggio Group Americas supported this interest with the launch of a “Vespanomics” website and platform, claiming lower per-mile carbon emissions of 0.4 lb/mile (113 g/km) less than the average car, a 65% reduction, and better fuel economy.[84]

    However, a motorcycle’s exhaust emissions may contain 10–20 times more oxides of nitrogen (NOx)carbon monoxide, and unburned hydrocarbons than exhaust from a similar-year passenger car or SUV.[82][85] This is because many motorcycles lack a catalytic converter, and the emission standard is much more permissive for motorcycles than for other vehicles.[82] While catalytic converters have been installed in most gasoline-powered cars and trucks since 1975 in the United States, they can present fitment and heat difficulties in motorcycle applications.[82] [better source needed]

    United States Environmental Protection Agency 2007 certification result reports for all vehicles versus on highway motorcycles (which also includes scooters),[86] the average certified emissions level for 12,327 vehicles tested was 0.734. The average “Nox+Co End-Of-Useful-Life-Emissions” for 3,863 motorcycles tested was 0.8531. 54% of the tested 2007-model motorcycles were equipped with a catalytic converter.

    United States emissions limits

    [edit]

    The following table shows maximum acceptable legal emissions of the combination of hydrocarbons, oxides of nitrogen, and carbon monoxide for new motorcycles sold in the United States with 280 cc or greater piston displacement.[87]

    TierModel yearHC+NOx (g/km)CO (g/km)
    Tier 12006–20091.412.0
    Tier 22010 and later0.812.0

    The maximum acceptable legal emissions of hydrocarbon and carbon monoxide for new Class I and II motorcycles (50 cc–169 cc and 170 cc–279 cc respectively) sold in the United States are as follows:[87]

    Model yearHC (g/km)CO (g/km)
    2006 and later1.012.0

    Europe

    [edit]

    European emission standards for motorcycles are similar to those for cars.[88] New motorcycles must meet Euro 5 standards,[89] while cars must meet Euro 6D-temp standards. Motorcycle emission controls are being updated and it has been proposed to update to Euro 5+ in 2024.[90]

    Asia

    [edit]

    In Asia, motorcycles are a common mode of transportation and are putting significant pressure on the region’s environment.[91][92] With a massive number of motorcycles, they contribute significantly to greenhouse gas emissions and urban air pollution.[92][93] In India, road transport accounts for about 12% of the country’s energy-related CO₂ emissions.[94] In Vietnam, motorcycles contribute up to 87% of the CO emissions and 94% of hydrocarbons (HC) released by vehicles in Hanoi and Ho Chi Minh City.[95][96][97] Environmental studies show that motorcycles in Vietnam contribute approximately 29% of NOx, 90% of CO, 65% of NMVOC, and nearly 38% of PM dust in total traffic emissions.[98][99][100] In Thailand, gasoline-powered motorcycles are reported to emit significantly higher pollution per kilometer compared to gasoline-powered cars, exacerbating urban smog.[101][102] In Singapore, the NEA reported that while motorcycles account for only 15 percent of vehicles, they contribute to over 53 percent of carbon monoxide emissions from vehicles.