bpm –  Beats per minute. The usual measurement of tempo.

BCD (binary coded decimal) – A coding system in which each decimal digit from 0 to 9 is represented by four binary (0 or 1) digits.

BNC – An acronym that is said to stand for  (a) British Naval Connector; (b) Bayonet Neill-Concelman; and (c) bayonet fitting connector.  1. Some sources say that this type of cable connector is “used exclusively in television”; others, that it is “used extensively in television and named for its inventor”; and still others, that it is “a professional type of video connector featuring a two-pin lock”, “with a bayonet lock used with coaxial video cable.” 2. This is a durable “professional” cable connector, which attaches to VCRs for transfer of high-frequency composite video in/out signals. Connects with a push and a twist.

BPI – Bits per Inch, usually referring to magnetic tape recording density.

bwf -Broadcast Wave Format  extension.  Microsoft WAVE audio format  is the recording format of most file-based non-linear digital recorders used for motion picture, radio and television production. It was first specified by the European Broadcasting Union in 1997, and updated in 2001 and 2003. The purpose of this file format is the addition of metadata to facilitate the  exchange of sound data between  computer platforms and applications. It specifies the format of metadata,  audio processing elements, and permits synchronization with other recordings. This metadata is stored as extension chunks in a standard digital audio WAV file. Files conforming to the Broadcast Wave specification have names ending with the extension .wav. The BWF is a development of the existing WAVE format, used on many DAWs and computers. A WAVE file is an audio file which is one type of the more general RIFF (Resource Interchange File Format) file. RIFF has been developed by the IBM and Microsoft corporations. A BWF file is a restricted subset of possible WAVE files but it also contains an extra “chunk” to carry information about the content. A “chunk” is a self contained collection of data in a RIFF file. It contains a header, which gives its type and length, followed by data arranged in fixed or variable length fields.

B-Movie – A low-budget, second tier movie, frequently the 2nd movie in a double-feature billing. B-films were cheaper for studios because they did not involve the most highly paid actors or costly sets, and were popular with theater owners because they were less expensive to bring into their theaters while still able to draw revenue.

B negative – Film term referring to takes not originally intended to be oriented from dailies but later called to be printed. This term has been carried over into videotape and refers to non-circle takes that are later transferred as alternative takes.

B-roll – Cutaway shots which are used to cover the visual part of an interview or narration. The term is often used in TV news.

B Wind – When you hold a roll of 16 mm or other single-perf film so that the film leaves the roll from the top and toward the right; the perforations will be along the edge away from the observer.

backplane – Rear connector channel, motherboard. The physical area, usually at the rear of an electronics frame, where modules and cables plug into the system.

back focus – The distance from the rear element of a lens to the image plane on the camera.

back light – Illumination from behind, creates sense of depth by separating foreground subject from background area. Applied erroneously, causes severe silhouetting. See fill light, key light, three-point lighting.

back porch – 1. The portion of a video signal that occurs during blanking from the end of horizontal sync to the beginning of active video. 2. The blanking signal portion which lies between the trailing edge of a horizontal sync pulse and the trailing edge of the corresponding blanking pulse. Color burst is located on the back porch.

back projection – also rear projection. A photographic technique whereby live action is filmed in front of a screen which the background action is projected on. Originally used for scenes occurring in vehicles. Contrast this with a matte shot.

back timing – Marking an “In” and “Out” point on a source clip and an “OUT” point in a program then allowing the edit software to calculate the “In” point on the program. This is also known as a “3 Point Edit”.

Background Artist – also Scenic Artist, Backgrounds. A person responsible for designing or constructing the art placed at the rear of a set. See also matte artist.

backing – 1. Coating applied to the base side of original negative film base. This coating is designed to absorb any light from passing through the emulsion during exposure. 2. Coating (e.g. anti-abrasion coating, anti-curl, or remjet backing) applied to the base side of the film to improve characteristics and performance.

backlot – also back lot. A large, undeveloped area on studio property used for constructing large open-air sets or for filming wilderness scenes.

backup – Copying files or databases so that they will be preserved.

backup supply – A redundant power supply that takes over if the primary power supply fails.

balanced – 1. A circuit having two sides (conductors) carrying voltages which are symmetrical around a common reference point, typically the ground.  2. a circuit in which two branches are electrically alike and symmetrical with respect to a common reference point, usually the ground; preferred to an unbalanced circuit due to its ability to reject noise.

banding –  Smooth graduated colors reduced to larger blocks of color. This produces a visible stepping of shades in the image.

bands – a grouping or range of frequencies.

bandwidth — 1. a collection or group of frequencies.  2. a measure of information carrying capacity without distortion.  3. Data throughput, meaning the amount of data sent. The term describes the amount of information that can be transmitted over a wire, line or wireless method of linking communication devices. Therefore, it defines the range of transmission frequencies a network can use. The greater the bandwidth is, the larger is the amount of information that can be transferred over that network.  4. The available “opening” through which information can pass. In audio, the bandwidth of a device is the portion of the frequency spectrum that it can handle without significant degradation. In digital communications, the bandwidth is the amount of data that can be transmitted in a given period of time.  5. The complete range of frequencies over which a circuit or electronic system can function with minimal signal loss, typically less than 3 dB. The information carrying capability of a particular television channel. In PAL systems the bandwidth limits the maximum visible frequency to 5.5 MHz, in NTSC, 4.2 MHz. The CCIR (TIU-R) 601 luminance channel sampling frequency of 13.5 MHz was chosen to permit faithful digital representation of the PAL and NTSC luminance bandwidths without aliasing.  6. The speed and amount of data that can be transferred in a given period of time. Higher bit rates mean higher quality media can be streamed or played back. Overall bandwidth depends upon the processing speed of your computer, along with the network or Internet connection. 7. The amount of audio or radio spectrum required or used by a signal or waveform.

bandwidth limiting – the result of encoding a higher quality signal into a lower quality form, such as RGB converted into S-Video.

bank – 1. A set of patches. 2. Any related set of items, e.g., a filter bank (a set of filters that work together to process a single signal). 3. a connected set of objects or filters that combine to produce one signal.

banned – Many countries have either government or official movie classification boards who are responsible for determining the suitability of a movie for release in their country or region. These boards occasionally block the release of a movie either in theaters or on video. Often, a banned movie will find its way around a ban by means of bootleg distribution. See also censorship.

barn door – also barndoor(s). 1. Accessory for video lights, one-, two- or fourleaf folding metal flaps attached to the front of a lamp housing to prevent light from spilling outside a desired area, to control light distribution.

base – The transparent, flexible support, formerly cellulose triacetate (in motion picture cameras), that holds the emulsion coating, which photographic emulsions are coated to make photographic film.

baseband – video signal that has not been modulated.

base plus fog – Density of the film support plus the silver or dye produced by the effects of the developer. Pertains only to an unexposed portion of the film.

baud rate – baud. Simplified from its technical meaning, it means bits persecond.  Hence kilobaud or Kbaud, thousands of bits per second. The technical meaning is level transitions per second'; this coincides with bps only for two-level modulation with no framing or stop bits. You will see the phrase "baud rate" in multimedia glossaries and dictionaries, but it is incorrect, since 'baud' already means 'a rate', similar to saying "ATM machine" when the 'M' in 'ATM' already stands for 'Machine'.  2. (music) how fast digital information is transmitted. Informally, the number of bits of computer information transmitted per second. MIDI transmissions have a baud rate of 31,250 (31.25 kilobaud), while modems typically have a much lower rate of 2,400, 9,600 (almost exactly one character per millisecond), or 14,400 baud.  Historical note:baud’ was originally a unit of telegraph signalling speed, set at one pulse per second. It was proposed at the International Telegraph Conference of 1927, and named after J.M.E.Baudot (1845–1903), the French engineer who constructed the first successful teleprinter.

bayonet – Mount used on most cameras to secure the lens on the body by using a lens fixing ring. Could also be an electrical connector.

behind the scenes – The off-camera goings on associated with film making.

Bell And Howell perforation (BH) –  A film perforation shaped with flat top, flat bottom, and curved sides.

below-the-Line expenses – All physical production costs not included in the above-the-line expenses, including material costs, music rights, publicity, trailer, etc.

bend  – To change pitch in a continuous sliding manner, usually using a pitch-bend wheel or lever. See pitch-bend.

bend radius – maximum amount a conductor can be bent before excessive attenuation is encountered, signal integrity is compromised, or the conductor breaks.

Best Boy – Assistant Chief Lighting Technician, Best Boy Grip, Best Boy Electric. The chief assistant, usually of the gaffer or key grip. In charge of the people and equipment, scheduling the required quantities for each day’s work. The term originates from promoting the crew’s ‘best boy’ to supervising, allowing the gaffer and key grip to stay on set and carry out the cameraman’s lighting needs. The origin of the term is from “pre-union” filming days when the line between Grip and Electric departments was less rigid. When the head of either department needed another body temporarily, he’d go to the head of the other department and ask him to “lend me your BEST boy”. By default the 2nd in charge of either department came to be known as best-boy. This term may also have been borrowed from early sailing and whaling crews, as sailors were often employed to set up and work rigging in theatres. There are no “best girls” per se; female chief assistants are also called “Best Boys”.

Beta – Informal name for Betacam, a professional color difference videotape recording format that uses the Y, R-Y, and B-Y color difference components. Also the name of a consumer videotape recording format that is completely different from the professional Betacam format.

Betacam – 1. Portable camera/recorder system using 1/2-inch tape originally developed by Sony. The name may also refer just to the recorder or the interconnect format; Betacam uses a version of the Y, R-Y, B-Y color difference signal set. Betacam is a registered trademark of the Sony Corporation.  2. A component broadcast system using half-inch tape and cases similar to those for the Beta format. 3. The most common broadcast quality video format of the past. Also Betacam SP, the enhanced version. “Legacy” formats.

Betacam SP – A superior performance version of Betacam. SP uses metal particle tape and a wider bandwidth recording system. This is a ‘legacy’ system.

Betamax – The obsolete home video format. Lost the format battle to VHS even though it was slightly superior. The cassette size,however, went on to become Betacam.

Bezier curve – 1. A spline is a curve which is defined mathematically and has a set of control points. A Bézier spline is a cubic spline which has four control points, where the first and last control points (knots or anchors) are the endpoints of the curve and the inner two control points (handles) determine the direction of the curve at the endpoints. 2. In the non-mathematical sense, a spline is a flexible strip of wood or metal used for drawing curves. Using this type of spline for drawing curves dates back to shipbuilding, where weights were hung on splines to bend them. The outer control points of a Bézier spline are similar to the places where the splines are fastened down and the inner control points are where weights are attached to modify the curve. 3. In 3D modeling, a curve with at least four control points available to control shape of the curve. This term may also refer to a NURBS curve. Bézier splines are only one way of mathematically representing curves.  They were developed in the 1960s by Pierre Bézier, who worked for Renault.

Bezier patch – In 3D modeling, a parametric surface, approximately rectangular, that is quilted together with other Bezier patches to form a large, curved surface. The shape of a Bezier patch is controlled by 16 control points distributed uniformly over the surface. Also known as patch surface.

bidirectional – Microphone pickup pattern whereby sound is absorbed equally from two sides only. It is designed to pick up sound on two sides of the microphone along the same axis, but reject sound from any other direction. See omnidirectional, unidirectional.

bi-directional polar pattern – the shape of the region where some microphones will be most sensitive to sound from the front and rear, while rejecting sound from the top, bottom and sides.

bilinear filtering – In 3D modeling, a method of anti-aliasing texture maps. A texture-aliening artifact occurs due to sampling on a finite pixel grid. Point-sampled telexes jump from one pixel to another at random times. This aliening is very noticeable on slowly rotating or moving polygons. The texture image jumps and shears along pixel boundaries. To eliminate this problem, bilinear filtering takes a weighted average of four adjacent texture pixels to create a single telex.

bin – On non-linear editing systems the bin is an organization tool for one or more film scenes.

biographic picture – or biopic. A filmed story of a person’s life story.

birefringence – A measurement of the stresses within the polycarbonate substrate of a Compact Disc. These stresses are introduced during moulding process. Philip’s Red Book states the maximum allowable birefringence is + 100nm. (nanometers).  See also Red Book

bit – Short for “Binary digIT”. The smallest piece if binary digital data and is represented by either a “1” or a “0”. Numbers of bits are used in digital video as a representation of signal quality (i.e. an 8-bit signal can have 256 levels from black to white while a 10-bit signal can have 1024 levels). Digital audio is encoded in words that are usually eight, 12, or 16 bits long (the bit resolution). Each added bit represents a theoretical improvement of about 6dB in the signal-to-noise ratio.

bitBLTs – A graphics operation in which two bitmap patterns are combined into one – and the single most important acceleration function for windowed GUI environments. A BitBLT is simply the movement of a block of data from one place to another, taking into account the special requirements and arrangements of the graphics memory. Operations handle patterns – usually square – and produce them at different locations on the screen. For example, this function is utilised every time a window is moved; in which case, the BitBLT is a simple Pixel Block Transfer. More complicated cases may occur where some transformation of the source data is to occur, such as in a Color Expanded Block Transfer, where each monochromatic bit in the source is expanded to the color in the foreground or background register before being written to the display.

bit depth – the number of bits used to describe data. The bit depth is an indication of the color depth that a pixel in a digital image may have. For example, when the image is available in 8 bit, each pixel in the image will provide one of 256 colors (28); when the image is in 10 bit, up to 1024 colors (210) are available.  2. The number of possible color values used in a digital image. A higher bit depth improves the tonality of an image because there are more color values to choose from.  3. The number of data bits used for each individual sample. The amount of bits determines the number of discrete levels possible to place a sample within. 8-10 bit is common for video; 16-24 bit is common for audio. See also my Image Glossary for more about color, bitdepth, and images.  3. Also known as Word Size. The number of computer bits present in each audio sample. Determines the dynamic range of the audio. 4. the number of bits per second that can be transported or processed; usually expressed as ‘bits per second’ (bps) or ‘Megabits per second’ (Mbps), and is the result of sampling rate multiplied by the number of data bits per sample (or bit depth), plus any additional data such as tracking information. Audio and highly compressed video runs in the Kilobits per second range. Other video compressed through different codecs may play at Megabits per second rates, usually because they are playing back higher quality content. Newer codecs, such as H.264, are more sophisticated and very efficient. They can operate at lower bits rates, but still deliver excellent quality video and audio. See also Jae Kamel’s Dictionary for more about bit depth.

bit part – A small unimportant role, usually lasting only one scene.

black a tape – The process of recording a black burst signal across the entire length of a tape. Often done before recording edited footage on the tape to give the tape clean, continuous video and sync and to insure there is no video already on the tape.

black and white – BW, B/W, B&W. Indicates that the images have no color. The first movies were black and white (as color film stock hadn’t been invented), but in more recent times many films have been shot in black and white either for artistic reasons or because it is cheaper. Some films are shot using color film stock with the final print in black and white.

black-and-white film – A film that produces a monochromatic picture in shades of gray (usually a metallic silver image).

black balance adjustment – Is done in order to assure that black has no color. The camera balances the black levels of the R, G and B channels.

black box – Generic term for wide variety of video image manipulation devices with perceived mysterious or “magical” capabilities, including proc amps, enhancers, SEGs, and TBCs.

black burst – 1. A composite video signal consisting of all horizontal & vertical synchronization information. It is typically used as the house reference synchronization signal in television facilities.  2. A composite color video signal comprised of sync, color burst and black video. Used to synchronize (genlock) other video sources to the same sync and color information. Black burst generators are used in editing systems “lock” the entire facility to a common signal (“house sync” or “house black”).

black comedy – A comedy in which the humour is derived from subjects which are typically considered “serious”, or for which humor is usually considered as unsuitable. Common examples are death, war, suffering, and murder.

blackface – The make up technique of making an actor, usually Caucasian-American, to resemble an African-American or at least a caricature thereof such as in the final scene of The Jazz Singer (1927). There were also equivalents for Asians (Yellowface) and American Indians (Redface). It was a standard practice in the early 20th century for the casting of actors in non-white roles and abandoned when it was recognized to be an insult to minorities which also cheated them of casting opportunies.

black level – voltage in a video signal which corresponds to black.

blacklisting – to blacklist. A list of filmmakers or actors who have either been formally or informally discriminated against, due to their personal, political, social, or religious beliefs. In 1950s America, McCarthyism resulted in numerous filmmakers, musicians, and writers being blacklisted.

black set – A reference level for black balance adjustment.

blanking interval (horizontal & vertical) – 1. The horizontal blanking interval is the time between the end of one scan line and the beginning of the next.  2. The vertical blanking interval is the time between the end of one video field and the beginning of the next. Blanking occurs when a monitor’s electron beam is positioned to start a new line or a new field. The  blanking interval is used to instantly reduce the beam’s amplitude so that the return trace is invisible. The screen goes blank for a fraction of second. See vertical interval switching.

blanking level – Also known as the pedestal, it is the voltage level produced at the end of each horizontal picture line which separates the portion of the video signal containing the picture information from the portion containing the synchronizing information. This voltage makes the electron beam “invisible” as it moves to draw the next visible line.

bleach – 1. Converting a metallic silver image to a halide or other salt that can be removed from the film with hypo. When bleaching is not carried to completion, it is called reducing. 2. Any chemical reagent that can be used for bleaching.

bleeding – Video image imperfection characterized by blurring of color borders; colors spill over defined boundaries, “run” into neighboring areas. See also trap .

block – A unit of data comprising of 588 bits. There are 7350 blocks in each second of information on a Compact Disc.

block diagram – an illustration of the signal path through a given system.

blocking – 1. pieces of wood that have been inserted between structural building elements to provide a secure mounting point for finish materials or products. 2. A process during which the director and actors determine where on the set the actors will move and stand, so that lighting and camera placements may be set.

blooper – See also out-take. A take of a scene not used in a movie, usually because of an on-camera mistake made by the cast or crew.

blowdown – Reducing a larger format to a smaller format. An example of blowing down would be going from Super 16 down to 16 mm.

blowup – Occurs when a smaller film format is increased to a larger format. An example would be going from Super 16 up to 35 mm.

blow-up printing – Optical printing resulting usually in a larger print image size from the original negative.

blue screen – 1. A color screen (sometimes green screen) used in post production for filming or video taping an object where the background will be replaced with another element.  2. A special effects procedure in which a subject is photographed in front of a uniformly illuminated blue or green background. A new background image can be electronically substituted for the blue or green during the shoot or in post-production through the use of chroma key to convert analog video to digital form.   3. A process whereby actors work in front of an evenly lit, monochromatic (usually blue or green) background. The background is then replaced in post production by chromakeying, allowing other footage or computer-generated images to form the background imagery. See also greenscreen.

Blu-ray – (pronounced blue-ray) A high definition video standard of 1080p at 1920 x 1080 resolution, primarily used for playing back Hollywood movies. The Blu-ray specification currently allows for very high bit rates, up to 40 Megabits per second. Blu-ray discs must be encoded in H.264, MPEG-2 or the VC-1 codec.

body double – also Photo Double. For some shots, a director may consider that a particular actor’s body may not be suitable for the impression desired. In these situations, the actor is “doubled” (replaced) by a person whose body is more suitable, and closely resembles the actor’s. Typically, body doubles are used for shots requiring nudity or depictions of physical fitness.  Contrast with stunt double and stand-in.

body makeup – Makeup applied below the neck or above the wrists.

boom – An overhead pole device used to position a microphone close to the actors, but out of the shot. A ‘fishpole’ is the portable version.

boom microphone – also Boom Mic, Boom, Fishpole, Giraffe. 1. A long pole with a microphone on the end. The boom is extended out near the actors. Ideally, the microphone at the end should be placed in the camera’s safe area. 2. Any microphone, but usually a unidirectional or shotgun microphone, attached to a pole or boom to keep the microphone near an audio source but outside of the field of view.

Boom Operator – A member of the sound crew who operates the boom microphone. See also Sound Recordist.

booming – Camera move above or below subject with aid of a balanced “boom arm,” creating sense of floating into or out of a scene.

bomb – A movie which is a financial disaster. Exception: in the United Kingdom, when used with “down” (e.g. “went down a bomb”), the term means a rousing success.

bootleg – An unofficial and illegally copied or distributed version of a movie, often of a substandard quality. Bootleg videos are often available for movies that have yet to be released in a particular country, or have been banned.

bounce board – A large white card made of foam or posterboard used to reflect soft light and for the soft key and fill.

boundary microphone – a microphone that relies on reflected sound from a surrounding surface.

Breakdown script – or Breakdown. A detailed list of all items, people, props, equipment, etc required for a shoot on a day-by-day basis. Recording such lists aids in continuity and allows optimization of the time of actors and the crew.

breaking the frame –  Stereo objects in front of the screen plane (negative parallax) are problematic if they intersect the edge of frame, as contradictory depth cues are sent to the viewer. Essentially one cue is saying that the object is in front of the screen and another is saying that the object is behind it. This problem can be reduced in Post by a technique known as a ‘floating window’. This involves applying a partially transparent mask on the left of the left image and on the right of the right image, reducing the strength of the cues on which ever side the object is breaking frame (and simultaneously if there are objects breaking frame both left and right). Another kind of issue is caused by objects moving backwards and forwards over the edge of frame. As an object moves off the  edge of a screen one stereo camera signal is lost before the other. The result is that the stereo signal temporarily ‘switches off’. This can sometimes be solved by sizing up both images in Post, causing the object to move off screen altogether. Objects breaking the frame aren’t necessarily a problem. It happens in IMAX all the time and also is common in conventional stereo films – the audience is encouraged to concentrate away from such an object by well thought out shooting.

breakout box – A box to be connected to a computer system to provide further connections. In a digital video environment a breakout box may provide further connections for the video system, for example, to in- or output audio or video.

breakout cable – At hardware (e.g. a video system) input /output connections that are usually distributed over several standardized connectors can be combined and offered via a single connector for the sake of space.

brick-wall filter –  A lowpass filter at the input of an analog-to-digital converter, used to prevent frequencies above the Nyquist limit from being encoded by the converter. See Nyquist frequency, aliasing.

bridge – A type of network circuit used to match circuits to each other, ensuring minimum transmission impairment. To place one circuit in parallel with another.

brightness control – A control used to adjust the illumination of viewfinders, monitors, and receivers, but not affecting signal levels from cameras or other picture sources.

broadband – 1. Having an essentially uniform response over a wide range of frequencies. Capable of handling frequencies greater than those required for high-grade voice communications (higher than 3 to 4 kilohertz).  2. Generally, connections to the Internet with much greater bandwidth than you can get with a modem. There is no specific definition of the speed of a  “broadband” connection but in general any Internet connection using DSL or a via Cable-TV may be considered a broadband connection.

broadcast quality – 1.Footage that meets the high technical standards for broadcast or cablecast. Quality that does not meet this standard is referred to as “reference quality”.  2. A nebulous term used to describe the output of a manufacturer’s product. Usually at least means that the technical specifications meet the FCC rules for broadcasting.

buffer – 1. An area or block of memory,used for recording or editing data before it is stored in a more permanent or lasting form. 2.  A circuit or component which isolates one electrical circuit from another.   3.  A digital storage device used to compensate for a difference in the rate of flow of information or the time of occurrence of events when transmitting information from one device to another.  4. In telecommunications, a protective material used in cabling optical fiber to cover and protect the fiber. The buffer material has no optical function.

buffer amplifier – an electronic device that provides some isolation between other components.

bulk dump – See data dump.

bump mapping – In 3D modeling, a technique where at each pixel, a perturbation to the surface normal of the object being rendered is looked up in a height-map and applied before the illumination calculation is done. The result is a richer, more detailed surface representation.

burn  – 1. Part of a pickup tube that has a depletion of charge evidence by a negative image of the picture source causing the depletion. This condition is temporary unless the tube is turned off and allowed to cool before the problem is corrected.  2. General term meaning recording data to special CD, DVD or Blu-ray media. It’s called ‘burning’ because a laser melts a special chemical layer in the recordable media to create pits and bumps, which reflect light different to mimic digital data.  Commercially produced movies are created through a different way called replication, where a mechanical stamping process makes the pits and bumps.

burn-in – Burn-in means to superimpose certain information on another image. With such a feature you can provide each image with individual information such as timecode, frame or keycode data or comments.

burst error – Consecutive block errors. Burst errors are usually the result of fingerprints, contamination, scratches, or voids, etc. The maximum value of any single burst error must not exceed 5.

bus – 1. A bus (or buss) is a group of data, control and/or addressing lines that extend from device to device and act as a conduit for signals. A Bus is often shared by several devices.  2. A wiring system that delivers power and data to various devices.  3. A central conductor for the primary signal path. A signal path to which a number of inputs may be connected for feed to one or more outputs.

button per source – A control panel which has a separate button for each source. Also called button per function.

bypass relay – A relay used to bypass the normal electrical route in the event of power, signal, or equipment failure.

bypass switcher – An audio-follow-video switcher usually associated with a master control switcher. Used to bypass the master control switcher output during emergencies, failures, or off-line maintenance.

byte – 1. an 8-bit word is called a byte. The acronym for byte is the upper-case B.   2.  MIDI bytes consist of ten bits because each byte includes a start bit and a stop bit, with eight bits in the middle to convey information.)