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Algorithm - A procedure for accomplishing a given result by proceeding on a logical step-by-step basis. Computer programs and N/C routines for machine tools are developed this way.

Analog - Computers of this type are designed to respond and control continuous process operations such as flows, temperatures, or other infinitely variable-type operations. Digital computers process only discrete digital data.

Automatic - Functioning in a predefined manner with a minimum of reprogrammability; possesses only limited process information closure.

Autonomous - Functioning independently of other components or systems; self-governing or self-controlling; possessing virtually complete closure in normal operation.

Axis - A general direction of relative motion between N/C machine cutting tool and the workpiece.

Bit - A binary digit of 0 or 1; the smallest unit of information.

Bootstrap - A technique for loading the first few instructions of a computer program into active memory and then using them to bring in the rest of the program.

Buffer Storage - A place for storing information in either a computer or control unit so that it is immediately available for action once the previous instructions have been completed. Buffers eliminate the need to wait for information to be transferred from a slower bulk storage medium into active memory.

Byte - A series of binary digits organized to represent an alphanumeric symbol; sometimes called a "word" of memory; 4-, 8-, and 16-bit bytes are common in computing.

CAD - Computer-aided design; the use of computers to aid in product design and development.

CAM - Computer-aided manufacturing; the use of computers to assist in any or all phases of manufacturing. N/C is one form of CAM.

Cartesian Coordinates - A system of two or three mutually perpendicular axes along which any point may be located in terms of distance and direction from any other point.

CAT - Computer-aided testing; the use of computers to aid in the testing of manufactured output.

Chip - Small piece of semiconductor material upon which electronic components and subassemblies are formed. Integrated circuits, LSI and VLSI are made on chips.

Closed-Loop System - A system whereby signals from a control unit are acted upon by the machine effector or teleoperator, and a monitoring unit then returns the acted upon signals for comparison; operates using feedback from errors, thus achieving some level of self-correction; opposite of open loop.

Closure - Exists when system function or output exceeds system structure and input requirements. Closure may involve quality, quantity, or throughput rate, and may apply to mass (parts, materials), energy (power, collectors), or information (assembly operations, repairs).

Cognition - Programmed models which approximate the behavior of natural cognition, in the context of robotic and artificial intelligence systems.

Compatibility - The degree to which tapes, languages, and programming can be interchanged among various computer-controlled systems.

CPU - Central processing unit; the basic memory or logic center of a computer that includes the circuits controlling the processing and execution of instructions.

CRT - Cathode ray tube; an electronic vacuum tube containing a screen on which graphic or alphanumeric information may be displayed.

CS&amp;T - Computer Science and Technology.

Dedicated Computer - A computer devoted exclusively to a single application.

Degrees of Freedom - The state of a mechanism can be described by specifying the current value of each variable parameter, particularly rotating or sliding elements, of robot systems.

Digital - Information and values are expressed in discrete terms. In a digital computer such terms are generated by a combination of binary on/off or positive/negative signals, the opposite of analog wherein a fluctuating signal strength determines the fluctuations of values.

Digitize - The process of converting a scaled, but not nonmathematical, image into digital data.

Disc - A random-access storage component of a computer system.

DOD - Department of Defense.

DOC - Department of Commerce.