N

NAB (A/V)
National Association of Broadcasters: an organization of radio and television station owners, equipment suppliers, and other firms involved in the broadcasting industry.

NABET (A/V)
National Association of Broadcast Employees and Technicians: Union for studio and master control engineers: also may include floor personnel.

NAK (communications)
Negative acknowledgement signal (see ACK-NAK). Used to indicate a message was not received, or that a terminal does not wish to transmit at this time.

Named Pipe (communications, DOS/WindowsNT)
Communications channel used by applications on Microsoft LAN Manager networks. It is an interprocess communications mechanism that allows one process to communicate with another local, or remote process.

NAMM (A/V, Music)
National Associated of Music Merchants - is an industry association of music dealers and musical instrument manufacturers. NAMM hold a yearly exhibition where new MIDI devices and audio components are introduced.

NAND (computer/microelectronics)
Logic operation which yields a logic "0" output when all logic input signals are logic "1". If any single input is false (0), then the logic operation is true (1).

Nanometer (communications, computer)
One billionth of a meter.

Nanosecond (communications, computer)
One billionth of a second. It is used to measure the speed of logic and memory chips. A nanosecond seems unbelievably fast, but it can be rationalized by converting it to distance. In one nanosecond, electricity travels about one foot; thus it can be visualized as a one-foot length of copper substrate. The advantage of a tiny chip is the decreased time electricity has to travel between circuits and logic elements. Electricity travels close to the speed of light (186,000 miles per second); yet, it is never fast enough for the hardware designer who will worry over an extra few inches of circuit path. The slightest delay is multiplied millions of times, since millions of pulses are sent in a single second.

NAPLPS (communications, computer)
American National Standards Institute (ANSI) adopted standard transmission format developed for graphics communications (into the home television) that did not become as popular as many envisioned at first. It compresses the graphics information for transmission over voice grade lines, but needs to be decompressed at the receiving end before viewing.

Narrow-Angle Lens (A/V)
Same as a long-focal-length lens: gives a narrow vista of a scene.

Narrowband Transmission (communications)
Term sometimes used to define bit speed transmission of less than 2,400 bits per second.

Native Language (computer)
Term sometimes used for machine language or binary language (see machine language).

Native Mode (computer)
Term sometimes used to describe a computer that is running machine language code. In personal computers, it can also mean that the computer is running in protected mode.

Natural Cutoff Lines (A/V)
In audio production, unwanted sounds that interfere with the intentional sounds; or unwanted hisses or hums inevitably generated by the electronics of the audio equipment. In video production, electronic interference that shows up as "snow" in the picture.

Natural Language Processing (computer)
Refers to the computer processing of natural language as "language", rather than as a meaningless string, or bit stream or letters or sounds. The key characteristic is "meaning". Natural language needs to be distinguished from artificial, formal languages. Natural languages are those such as Greek, English, Russian, Chinese Mandarin, as well as the languages of the First Peoples of North America, which people can learn, from birth, and be understood without having to have taken formal language training. Living, natural languages grow and change. In computer terms, an operational discourse would allow a person, knowing only the general capabilities of a system, with no training other than occasional clarifying dialogue with the system itself, can take the initiative in interacting with the system, and can make use of its complete capability, it could then be said that the system "understands" the natural language used in that domain.

Natural Light (A/V)
Sunlight, moonlight, or light filtered by overcast (term used in Audio/Visual production)

NAU (communications, computer)
Network Access Unit: interface card that adapts a computer to a local area network. Network Addressable Unit, Logical, Physical unit, system control under IBM SNA.

NCB (communications, computer)
Network Control Block: packet protocol used by NetBIOS transport layer.

NCP (communications, computer)
Network Control Program - a program that controls the traffic between multiple terminals and a mini or mainframe. It typically resides in a front end processor and performs such operations as polling the terminals.

NetWare Core Protocol - proprietary language used in Novell's NetWare to communicate between the workstations and the server. It is Netware's format for requesting and replying to requests for file and print services.

NCR (computer)
Acronym for NCR Corporation, started in 1884, and recently acquired by AT&T.

NCSC: (communications, computer)
National Computer Security Center, part of NSA (National Security Agency, U.S.), that defines standards for security-capable computer and communications products.

NDIS: Network Driver Interface Specification (communications, computer)
API (application program interface) by Microsoft and 3Com, used by LAN Manager and Banyan VINES for LAN adapter drivers. NDIS helps different operating systems and adapters to work together and provides multiple protocol stacks in the same host.

Near Field (A/V, Music)
Term describing a set of speakers designed to be located very close to the listener rather than to fill a room with sound. Near-field audio monitors have the advantage of minimizing the extraneous effects of room acoustics on the reproduced sound.

Near Letter Quality (computer/printing)
Appearance of printing produced by dot-matrix printers with 24-pin printheads.

Needle Drop (A/V, Music)
Piece of music rather than original composition for A/V use. It comes from the days of vinyl records. Needle-drop charges are paid to copyright owners for the music use.

Negative (computer/printing)
Reverse photographic image on paper or film (reverse of positive).

Negative Logic (computer)
Logic in which the more negative voltage represents the "1" state; the less negative voltage represents the "0" state.

Negative-Resistance Circuits (computer/microelectronics)
Circuits or devices whose static (dc) current-voltage characteristic at one or more ports has a range in which the slope is negative. Negative-resistance circuits and the circuits based upon them find many applications in counting or information storage, in the generation of pulses or alternating voltages, in instrumentation, in the control of current and power, and in physical realization of idealized (loss-less) or hypothetical circuits. Some of the different types of negative-resistance circuits include: astable, bistable, monostable, and sine-wave oscillators.

Nematic (computer/microelectronics)
Term sometimes used to describe a stage between a liquid and a crystal (liquid-crystal).

Neper (communications/computer)
Unit of attenuation used in transmission line theory. The word neper originated from a misspelling of the proper name of Napier. One neper equals 8,686 dB, the decibel being the practical unit of attenuation.

Nested (computer)
Procedures calling other procedures within an application. Called procedures are said to be nested within the calling procedure. When many calls to sub-procedures and sub-sub-procedures are made, the last one in the sequence is said to be deeply nested.

NetBEUI (communications, computer)
Network Extended User Interface - pronounced "net-booey" - the implementation of the NetBIOS transport protocol within LAN Manager and LAN Server. It communicates to the network interface cards (NICs) via NDIS (Network Driver Interface Specification). NetBEUI is used by Microsoft LAN Manager, Windows for Workgroups, Windows NT.

NetBIOS (communications, computer)
Transport protocol for PC local area networks, implemented in Microsoft's MS-Net and LAN Manager. Application programs use NetBIOS for client/server or peer-to-peer communications. There are two NetBIOS modes. The Datagram is the fastest method, but does not guarantee delivery of a message. It is a self-contained packet with sender and receiver name, usually limited to 512 bytes. If the recipient device is not listening for messages, the datagram is lost. Session mode establishes a connection until broken. It guarantees delivery of messages up to 64K bytes. NetBIOS-compliant protocols refer to layers 3,4, and 5 of the OSI model (Open System Interconnect). It is similar on some layers to Novell's IP and IPX. Some vendors use their own implementation of NetBIOS.

Net Logon Service (computer/WindowsNT)
For Windows NT Advanced Server, it performs authentication of domain logons, and keeps the domain's database synchronized between the domain controller and the other Windows NT Advanced Servers of the domain.

NetView (communications, computer)
IBM, SNA (System Network Architecture) network control programs (also NetView/PC)

NetWare (communications, computer)
Family of network operating systems from Novell, Inc. that runs on 286 and higher PCs and supports DOS, OS/2, Windows, Macintosh workstations. It also supports a large number of LAN access methods (Token Ring, Ethernet, ARCNET and Starlan). ELS NetWare (Entry Level System) Levels I and II run on 286 and higher CPUs and provide support for up to four and eight workstations respectively. ELS allows the server to function in the same machine as a workstation. The most widely installed NetWare operating system is Advanced NetWare which runs on a dedicated file server, and provides support for 100 users. NetWare is the sole control program in the server and does not co-exist with DOS. SFT NetWare (System Fault Tolerant) runs on a 286 and higher PC and provides automatic recovery from network malfunctions. NetWare 386 runs on 386s and higher file servers and provides increased functionality and performance. It supports up to 250 users with future potential for up to 4,000. NetWare for VMS provides NetWare connectivity to VAX (DEC) networks, and Portable NetWare provides fundamental NetWare services in source code for conversion to other hardware platforms.

NetWare Loadable Modules: NLMs (communications, computer)
Applications and drivers that run on a Novell NetWare server and can be loaded or unloaded on the fly.

Network (communications, computer)
In communications, the transmission channels and supporting hardware and software that make up a network (local, building, metropolitan, wide area, etc.). In microelectronics fabrication, a collection of elements, such as resistors, coils, capacitors, and sources of energy, connected together to form several interrelated circuits.

Network Adapter Card: NAC (communications, computer)
Circuit card required in the expansion bus of a workstation under IBM's PC Network.

Network Administrator (communications, computer)
An individual who is responsible for the operation of a communications network. The network administrator installs applications on the servers, monitors network activity and is generally responsible for its efficient operation.

Network Architecture (communications)
Design of a communications system, which includes the hardware, software, access methods and protocols used. It also defines the method of control, for example, whether computers can act independently or whether they are controlled by other computers that are constantly monitoring the network. Network architectures determine future flexibility and connectability to foreign networks.

Network DDE Services (communications, computer/WindowsNT)
Network Dynamic Data Exchange (DDE) service providing network transport and security for DDE conversations.

Network DDE DSDM Service (communications, computer/WindowsNT)
Network Dynamic Data Exchange, Share Database Manager service manages shared DDE conversations. It is used by the Network DDE service.

Network Device Driver (communications, computer)
Software coordinating communications between network adapter cards and computer hardware and other software, controlling physical functions of network adapter cards.

Network Directory (communications, computer)
Directory that network users can connect to.

Network Interface Card: NIC (communications)
Circuit board that can be inserted into a slot inside a personal computer to allow it to send and receive messages on a Local Area Network (LAN).

Network Layer (communications, computer)
Layer of the OSI LAN model that establishes protocols for packets, message, priorities, and network traffic control (Open System Interconnection, Local Area Network protocol).

Layer 3 of the OSI model; responsible for routing data through a communications network. (OSI = Opens Systems Interconnect).

Network Management (communications)
Monitoring of an active network in order to diagnose problems and gather statistics for network administration and optimization of all of the network components.

Network Operating System (communications, computer)
Control program that resides in a file server within a local area network. It handles the requests for data from all the users (workstations) on the network.

Network Terminating Equipment (communications)
Grouping of ISDN functions at the boundary between the ISDN and the subscriber.
(ISDN = Integrated Services Digital Network)

Network Theory (communications, microelectronics)
Generalization of the relations among the elements of an electrical network.

Neural Network (communications, computer)
Modelling technique based on observed behaviour of biological neurons. It is used to mimic performance of a system. It consists of a set of elements that start out connected in a random pattern, and, based upon operational feedback, are moulded into the pattern required to generate the required results. Neural networks are used in applications such as robotics, diagnostics, forecasting, image processing and pattern recognition.

Neutral (computer/printing)
Color that has no hue, such as white, gray, or black.

Neutral Density Filter (A/V)
Filter that reduces the incoming light without distorting the color of the scene.

Neutron Transmutation Doping (computer/microelectronics)
Introduction of certain impurity atoms into semiconducting by nuclear transmutation as a consequence of thermal neutron absorption in a nuclear reactor. Silicon is a particularly attractive candidate for transmutation doping because it has only one isotope which transmutes to a new element, phosphorus, a standard dopant in electronic fabrication.

Newline (computer)
Combination of a carriage-return (the Enter key, CR for Carriage Return, or ASCI character 13) and line feed (LF or ASCII character 10) used to terminate a line of text on screen or within a text file. Other characters or combinations may be substituted for the CR/LF pair to indicate the type of newline character (soft, hard, deletable, etc.)

Nibble (computer, microelectronics)
Group of four (4) bits operated upon as a unit.

NIC (communications, computer)
Network Interface Card - circuit board that plugs into a PC or network server and controls exchange of data over a network. the transmission medium (twisted pair, coax, or fiber optic cable) interconnects all the NICs in the network. The NIC performs the electronic functions of the access method, or data link protocol, such as Ethernet, Token Ring, etc.

Ni-Cad Battery (A/V)
Nickel-Cadmium, heavy-duty, multipurpose, portable, rechargeable batteries used in the field to power video tape, camera-recorder ensembles (stacked at times in battery packs).

NIST (communications, computer)
National Institute of Standards and Technology - the standards-defining agency of the U.S. government, formerly called the National Bureau of Standards.

NLM (communications, computer)
NetWare Loadable Module; program from Novell providing additional server functions, additional support for other products, other databases, other communications devices.

NLSFUNC (computer/DOS)
DOS Command that loads the National Language Support Function program, which DOS uses for country conventions and code page switching. It must be used before the user can invoke the CHCP command. If the code page is being changed, the user would enter a command as follows: NLSFUNC. After entering this command, the user is ready to invoke the CHCP to switch to another code page.

NMOS (communications, computer)
N-Channel MOS (metal oxide semiconductor) circuits, using current made up of negative charges and producing devices at least twice as fast PMOS).

Noble Metal Paste (computer, microelectronics)
Moist, smooth compound made up partially of precious metals such as gold, platinum, ruthenium, or others classed as noble metals, providing conductors in film circuitry.

Node (communications)
Device, such as a personal computer, hard disk, printer, or another peripheral, that is connected to a network (typically within a workgroup, the local area network).

Noise (A/V, communications)
Extraneous signals that invade a transmission. It can come from electrical or magnetic signals in nearby lines, from poorly fitting electrical contacts, and from power line spikes. In audio production, unwanted sounds that interfere with the intentional sounds; or unwanted hisses or hums inevitably generated by the electronics of the audio equipment. In video, electronic interference that shows up as "snow" on the picture.

Noise Filter in Radio (communications)
Filter used in communications receivers to reduce noise. Usually, it is an auxiliary low-pass filter which can be switched in or out of the audio system. The noise filter may also be equipped with a switch to vary the effective receiving bandwidth to meet the existing conditions of interfering noise. The tone control of a radio or record player can act as a noise filter, an when high-frequencies are cut down to reduce record noise. A bandpass filter may also be used, if the noise has a band-limited spectrum.

Noise Immunity (communications, computer/microelectronics)
Measure of insensitivity of a logic circuit to triggering or reaction to spurious or undesirable electrical signals or noise, largely determined by the signal swing of the logic. Noise can be either of two directions, positive or negative.

Non-Dedicated File Server (communications/LAN)
File server on a local area network, that also functions as an independent microcomputer.

Non-Drop Frame (A/V)
In Audio/Visual production, a term used to describe a form of SMPTE (Society of Motion Picture and Television Engineers) time code that runs in consecutively ascending numbers, even though it does not exactly match the actual elapsed time.

Nonimpact Printer (computer/printer)
Printer that prints without striking paper (laser printer, bubble jet, etc.).

Noninterlaced (A/V, computer)
Preferred method of displaying images, usually on a multisynchronous video display unit, where the image is created by displaying consecutive rather than alternate scanning lines.

Nonlinear Programming (computer/mathematics)
Area of applied mathematics concerned with finding the values of the variables which give the smallest or largest value of a specified function in the class of all variables satisfying prescribed conditions. The function which is to be optimized is called the objective function, and the functions defining the prescribed conditions are referred to as the constraint functions or constraints. This general problem is called the nonlinear programming problem. The study of the theoretical and computational aspects of the nonlinear programming problem is called nonlinear programming, or optimization theory.

Non-Noble System (computer/microelectronics)
Thick film system using conductors of copper, tungsten, nickel, molybdenum, and other non-noble metals (as opposed to a noble system using precious metals).

Nonprocedural Languages (computer)
Language employed by a user to indicate the goals to be achieved (what) rather than the specific methods used to achieve them (how). There are four features which are considered of major importance for including in a programming language that claims to be nonprocedural: (1) associated referencing; (2) aggregate operators; (3) elimination of arbitrary sequencing; (4) report program generators.

Non-Scalable Font (computer/printer)
Font designed for one size only: i.e. a raster font.

Nonsinusoidal Waveform (computer/microelectronics)
Representation of a wave that does not vary in a sinusoidal manner. Electric circuits containing nonlinear elements, such as electron tubes, transistors, commonly produce nonsinusoidal current and voltages. When these are repetitive functions of time, the are called nonsinusoidal electric waves.

Nonsymmetrical Division (A/V)
Framing a picture so distinct vertical objects are off to one side, rather than in the center, or so that the horizon is at the one-third or two-thirds mark, rather than the middle.

Non-volatile Memory (computer term)
Memory that holds content without power. Firmware chips (ROMs, PROMs, EPROMs, EEPROMs) are examples of non-volatile memory. Magnetic disks and tapes may also be classified as non-volatile memory; they are usually considered storage devices.

Non-Windows Application (computer)
Refers to an application that is designed to run with Windows 3.x, MS-DOS, OS/2, or POSIX, but not specifically with Windows (or with new Windows NT), and that may not be able to take full advantage of all Windows (or Windows NT) features.

NOR (computer/microelectronics)
Logic operation which yields a logic "0" output with one or more true "1" input signals. If all inputs are false (0) then the output is true (1), and vice-versa.

Normal Lens (A/V)
Lens with a focal length that will approximate the spatial relationships of normal vision when used with a particular film or camera pickup format.

Norton SI (computer)
Norton System Information - a Norton Utilities program that measures computer performance. It provides a computing index (CI) that measures CPU speed, a disk index (DI), for disk speed and a performance index (PI) that is a composite of the two.

Norton Utilities (computer)
Utility program for PCs from Symantec, Inc. The programs allow the user to restore deleted files on the disk, search and edit files no matter what format they are in and list and manage disk directories, among other things. Programs such as these provide an invaluable aid to both the novice and the advanced personal computer user.

NOS (communications, computer)
Network Operating System: term used by a number of vendors (Novell, Control Data).

Noseroom (A/V)
Space left in front of a person looking toward the edge of screen (also called leadroom).

NOT (computer/microelectronics)
Logic operation indicating negations, not "1". Actually an inverter. If input is "1", output is NOT "1" but "0". If input is "0", output is NOT "0", but "1": graphically represented by a bar over a Boolean symbol such as A (when A is marked means when A is not 1).

Note Off (A/V, Music, M/M)
MIDI message instructing a MIDI instrument to stop playing a specific note on an assigned channel. This message corresponds to the release of a key on a keyboard. The sound may continue for a short time after the Note Off signal.

Note On (A/V, Music, M/M)
MIDI message instructing a MIDI instrument to start playing a specific note on an assigned channel. This message corresponds to depressing a key on a keyboard. The intensity of the note is determined by the force applied to the key. The force is translated into a MIDI velocity byte that is added to the channel & note number bytes to form a Note On message set.

Notebook Computer
Portable computer usually less than 6 pounds, using Liquid Crystal Display technology.

Notepad Computer
Pen-based computer about the size of a notepad of paper.

Novell Network (communications, computer)
Local area network that is controlled by one of Novell's NetWare Operating Systems.

n-Region (computer/microelectronics)
Zone in a semiconductor in which electron density is greater than hole density.

NRM: Normal Response Mode (communications, computer)
When a centralized computer resource sends a poll bit to a station that wishes to transmit.

NRZ (communications, computer)
Non-Return-To-Zero: signalling method used in magnetic recording and communications that does not automatically return to a null point or zero reference point.

NSTL (computer)
National Software Testing Laboratory. Independent organization in Philadelphia that evaluates computer hardware and software. It adheres to controlled testing methods to insure accurate, objective results and publishes these results in Software Digest Ratings Report and PC Digest.

NTFS (computer/Windows)
Advanced File System for Windows NT operating system, it supports file system recovery, large storage media, and various features for the POSIX subsystem. It supports object-oriented applications & treats all files as objects with user-defined & system-defined attributes.

NTSC (A/V, communications, computer)
National Television Standards Committee - TV standard for the U.S., created by the NTSC and administered by the FCC. NTSC is 525 lines of resolution transmitted at 60 half frames (interlaced) per second. The signal is generated as a composite of red, green, and blue for color and includes an FM frequency for audio and an MTS signal for stereo: FM = frequency modulation; MTS = Modular TV System, the stereo channel added to NTSC TV standard, which includes SAP audio channel for special use; SAP = Secondary Audio Program - an NTSC channel used for auxiliary transmission (i.e., foreign language or teletext). NTSC sets standards for TV broadcasting in the Western Hemisphere (except Argentina, Brazil, Paraguay, and Uruguay), Japan and Korea. NTSC TV uses 525 line frames and displays full frames at 30/second. Frames consist of two interlaced fields displayed at 60 per second (U.S. power-line frequency of 60 Hz). Western European countries (except France) use the PAL standard based on their 50 Hz power-line frequencies (refer to PAL, RS-170-A, SECAM).

n-Type (computer/microelectronics)
Semiconductor material whose impurities produce free electrons, leading to conduction.

n-Type Semiconductor (computer/microelectronics)
Extrinsic (outward side) semiconductor: a semiconductor where the electron density exceeds the hole density (electron donor type).

Null (computer)
Variable of no value. 0 for numeric variables; an empty string ("") for string variables; or a long-integer 0 for pointers.

Null Character (computer)
Character in a character set or character code (i.e. ASCII, EBCDIC) with all bits of "0". Null is printed as a blank in decimal code and as 00 in hexadecimal code.

Null Modem Cable (communications, computer)
RS-232-C cable that is used to interconnect two personal computers that are in close proximity. The cable connects to the serial ports and crosses connections so that the sending wire on one end becomes the receiving wire on the other end.

Numeric Field (computer)
Field that contains numbers used for calculations.

Numerical Analysis (communications, computer)
Development and analysis of computational methods (and ultimately of program packages) for the minimization and the approximation of functions, and for the approximate solution of equations such as linear or nonlinear equations and differential or integral equations. Originally part of every mathematician's work, the subject is now often taught in computer science departments because of the tremendous impact which computers have had on the development of numerical analysis.