Chattanooga Software Center
 

Glossary of Computer Software Development Terminology

 

The terms are defined, as much as possible, using available standards. The source of such definitions appears immediately following the term or phrase in parenthesis, e.g. (NIST).

 

The source documents are listed at the bottom of this page.

 

 
  ABCDEFGHIJKLMNOPQRSTUVWXYZ  
     
 

RAM. random access memory.

 

RFI. radiofrequency interference.

 

RISC. reduced instruction set computer.

 

ROM. read only memory.

 

radiofrequency interference. High frequency electromagnetic waves that emanate from electronic devices such as chips and other electronic devices. An electromagnetic disturbance caused by such radiating and transmitting sources as electrostatic discharge [ESD], lightning, radar, radio and TV signals, and motors with brushes can induce unwanted voltages in electronic circuits, damage components and cause malfunctions. See: electromagnetic interference.

 

random access memory. Chips which can be called read/write memory, since the data stored in them may be read or new data may be written into any memory address on these chips. The term random access means that each memory location [usually 8 bits or 1 byte] may be directly accessed [read from or written to] at random. This contrasts to devices like magnetic tape where each section of the tape must be searched sequentially by the read/write head from its current location until it finds the desired location. ROM memory is also random access memory, but they are read only not read/write memories. Another difference between RAM and ROM is that RAM is volatile, i.e. it must have a constant supply of power or the stored data will be lost.

 

range check. (ISO) A limit check in which both high and low values are stipulated.

 

rapid prototyping. A structured software requirements discovery technique which emphasizes generating prototypes early in the development process to permit early feedback and analysis in support of the development process. Contrast with incremental development, spiral model, waterfall model. See: prototyping.

 

read only memory. A memory chip from which data can only be read by the CPU. The CPU may not store data to this memory. The advantage of ROM over RAM is that ROM does not require power to retain its program. This advantage applies to all types of ROM chips; ROM, PROM, EPROM, and EEPROM.

 

real time. (IEEE) Pertaining to a system or mode of operation in which computation is performed during the actual time that an external process occurs, in order that the computation results can be used to control, monitor, or respond in a timely manner to the external process. Contrast with batch. See: conversational, interactive, interrupt, on-line.

 

real time processing. A fast-response [immediate response] on-line system which obtains data from an activity or a physical process, performs computations, and returns a response rapidly enough to affect [control] the outcome of the activity or process; e.g., a process control application. Contrast with batch processing.

 

record. (1) (ISO) a group of related data elements treated as a unit. [A data element (field) is a component of a record, a record is a component of a file (database)].

 

record of change. Documentation of changes made to the system. A record of change can be a written document or a database. Normally there are two associated with a computer system, hardware and software. Changes made to the data are recorded in an audit trail.

 

recursion. (IEEE) (1) The process of defining or generating a process or data structure in terms of itself. (2) A process in which a software module calls itself.

 

reduced instruction set computer. Computer architecture that reduces the complexity of the chip by using simpler instructions. Reduced instruction set does not necessarily mean fewer instructions, but rather a return to simple instructions requiring only one or a very few instruction cycles to execute, and therefore are more effectively utilized with innovative architectural and compiler changes. Systems using RISC technology are able to achieve processing speeds of more than five million instructions per second.

 

region. A clearly described area within the computer's storage that is logically and/or physically distinct from other regions. Regions are used to separate testing from production [normal use]. Syn: partition.

 

register. A small, high speed memory circuit within a microprocessor that holds addresses and values of internal operations; e.g., registers keep track of the address of the instruction being executed and the data being processed. Each microprocessor has a specific number of registers depending upon its design.

 

regression analysis and testing. (IEEE) A software V&V task to determine the extent of V&V analysis and testing that must be repeated when changes are made to any previously examined software products. See: testing, regression.

 

relational database. Database organization method that links files together as required. Relationships between files are created by comparing data such as account numbers and names. A relational system can take any two or more files and generate a new file from the records that meet the matching criteria. Routine queries often involve more than one data file; e.g., a customer file and an order file can be linked in order to ask a question that relates to information in both files, such as the names of the customers that purchased a particular product. Contrast with network database, flat file.

 

release. (IEEE) The formal notification and distribution of an approved version. See: version.

 

reliability. (IEEE) The ability of a system or component to perform its required functions under stated conditions for a specified period of time. See: software reliability.

 

reliability assessment. (ANSI/IEEE) The process of determining the achieved level of reliability for an existing system or system component.

 

requirement. (IEEE) (1) A condition or capability needed by a user to solve a problem or achieve an objective. (2) A condition or capability that must be met or possessed by a system or system component to satisfy a contract, standard, specification, or other formally imposed documents. (3) A documented representation of a condition or capability as in (1) or (2). See: design requirement, functional requirement, implementation requirement, interface requirement, performance requirement, physical requirement.

 

requirements analysis. (IEEE) (1) The process of studying user needs to arrive at a definition of a system, hardware, or software requirements. (2) The process of studying and refining system, hardware, or software requirements. See: prototyping, software engineering.

 

requirements phase. (IEEE) The period of time in the software life cycle during which the requirements, such as functional and performance capabilities for a software product, are defined and documented.

 

requirements review. (IEEE) A process or meeting during which the requirements for a system, hardware item, or software item are presented to project personnel, managers, users, customers, or other interested parties for comment or approval. Types include system requirements review, software requirements review. Contrast with code review, design review, formal qualification review, test readiness review.

 

retention period. (ISO) The length of time specified for data on a data medium to be preserved.

 

retrospective trace. (IEEE) A trace produced from historical data recorded during the execution of a computer program. Note: this differs from an ordinary trace, which is produced cumulatively during program execution. See: execution trace, subroutine trace, symbolic trace, variable trace.

 

revalidation. Relative to software changes, revalidation means validating the change itself, assessing the nature of the change to determine potential ripple effects, and performing the necessary regression testing.

 

review. (IEEE) A process or meeting during which a work product or set of work products, is presented to project personnel, managers, users, customers, or other interested parties for comment or approval. Types include code review, design review, formal qualification review, requirements review, test readiness review. Contrast with audit, inspection. See: static analysis.

 

revision number. See: version number.

 

risk. (IEEE) A measure of the probability and severity of undesired effects. Often taken as the simple product of probability and consequence.

 

risk assessment. (DOD) A comprehensive evaluation of the risk and its associated impact.

 

robustness. The degree to which a software system or component can function correctly in the presence of invalid inputs or stressful environmental conditions. See: software reliability.

 

routine. (IEEE) A subprogram that is called by other programs and subprograms. Note: This term is defined differently in various programming languages. See: module.

 

RS-232-C. An Electronic Industries Association (EIA) standard for connecting electronic equipment. Data is transmitted and received in serial format.

 
     
 

Source Documents

 

  1. The New IEEE Standard Dictionary of Electrical and Electronics Terms, IEEE Std. 100-1992.
  2. IEEE Standards Collection, Software Engineering, 1994 Edition, published by the Institute of Electrical and Electronic Engineers Inc.
  3. National Bureau of Standards [NBS] Special Publication 500-75 Validation, Verification, and Testing of Computer Software, 1981.
  4. Federal Information Processing Standards [FIPS] Publication 101, Guideline For Lifecycle Validation, Verification, and Testing of Computer Software, 1983.
  5. Federal Information Processing Standards [FIPS] Publication 105, Guideline for Software Documentation Management, 1984.
  6. American National Standard for Information Systems, Dictionary for Information Systems, American National Standards Institute, 1991.
  7. FDA Technical Report, Software Development Activities, July 1987.
  8. FDA Guide to Inspection of Computerized Systems in Drug Processing, 1983.
  9. FDA Guideline on General Principles of Process Validation, May 1987.
  10. Reviewer Guidance for Computer Controlled Medical Devices Undergoing 510(k) Review, Office of Device Evaluation, CDRH, FDA, August 1991.
  11. HHS Publication FDA 90-4236, Preproduction Quality Assurance Planning.
  12. MIL-STD-882C, Military Standard System Safety Program Requirements, 19JAN1993.
  13. International Electrotechnical Commission, International Standard 1025, Fault Tree Analysis.
  14. International Electrotechnical Commission, International Standard 812, Analysis Techniques for System Reliability - Procedure for Failure Mode and Effects Analysis [FMEA].
  15. FDA recommendations, Application of the Medical Device GMP to Computerized Devices and Manufacturing Processes, May 1992.
  16. Pressman, R., Software Engineering, A Practitioner's Approach, Third Edition, McGraw-Hill, Inc., 1992.
  17. Myers, G., The Art of Software Testing, Wiley Interscience, 1979.
  18. Beizer, B., Software Testing Techniques, Second Edition, Van Nostrand Reinhold, 1990.
  19. Additional general references used in developing some definitions are:
  20. Bohl, M., Information Processing, Fourth Edition, Science Research Associates, Inc., 1984.
  21. Freedman, A., The Computer Glossary, Sixth Edition, American Management Association, 1993.
  22. McGraw-Hill Electronics Dictionary, Fifth Edition, 1994, McGraw-Hill Inc.
  23. McGraw-Hill Dictionary of Scientific & Technical Terms, Fifth Edition, 1994, McGraw-Hill Inc..
  24. Webster's New Universal Unabridged Dictionary, Deluxe Second Edition, 1979.


The bulk of this information was obtained from FDA.gov.

 

BIOS. basic input/output system.

 

bps. bits per second.

 

band. Range of frequencies used for transmitting a signal. A band can be identified by the difference between its lower and upper limits, i.e. bandwidth, as well as by its actual lower and upper limits; e.g., a 10 MHz band in the 100 to 110 MHz range.

 

bandwidth. The transmission capacity of a computer channel, communications line or bus. It is expressed in cycles per second [Hz], and also is often stated in bits or bytes per second. See: band.

 

bar code. (ISO) A code representing characters by sets of parallel bars of varying thickness and separation that are read optically by transverse scanning.

 

baseline. (NIST) A specification or product that has been formally reviewed and agreed upon, that serves as the basis for further development, and that can be changed only through formal change control procedures.

 

BASIC. An acronym for Beginners All-purpose Symbolic Instruction Code, a high-level programming language intended to facilitate learning to program in an interactive environment.

 

basic input/output system. Firmware that activates peripheral devices in a PC. Includes routines for the keyboard, screen, disk, parallel port and serial port, and for internal services such as time and date. It accepts requests from the device drivers in the operating system as well from application programs. It also contains autostart functions that test the system on startup and prepare the computer for operation. It loads the operating system and passes control to it.

 

batch. (IEEE) Pertaining to a system or mode of operation in which inputs are collected and processed all at one time, rather than being processed as they arrive, and a job, once started, proceeds to completion without additional input or user interaction. Contrast with conversational, interactive, on-line, real time.

 

batch processing. Execution of programs serially with no interactive processing. Contrast with real time processing.

 

baud. The signalling rate of a line. It's the switching speed, or number of transitions [voltage or frequency change] made per second. At low speeds bauds are equal to bits per seconds; e.g., 300 baud is equal to 300 bps. However, one baud can be made to represent more than one bit per second.

 

benchmark. A standard against which measurements or comparisons can be made.

 

bias. A measure of how closely the mean value in a series of replicate measurements approaches the true value. See: accuracy, precision, calibration.

 

binary. The base two number system. Permissible digits are "0" and "1".

 

bit. A contraction of the term binary digit. The bit is the basic unit of digital data. It may be in one of two states, logic 1 or logic 0. It may be thought of as a switch which is either on or off. Bits are usually combined into computer words of various sizes, such as the byte.

 

bits per second. A measure of the speed of data transfer in a communications system.

 

black-box testing. See: testing, functional.

 

block. (ISO) (1) A string of records, words, or characters that for technical or logical purposes are treated as a unity. (2) A collection of contiguous records that are recorded as a unit, and the units are separated by interblock gaps. (3) A group of bits or digits that are transmitted as a unit and that may be encoded for error-control purposes. (4) In programming languages, a subdivision of a program that serves to group related statements, delimit routines, specify storage allocation, delineate the applicability of labels, or segment parts of the program for other purposes. In FORTRAN, a block may be a sequence of statements; in COBOL, it may be a physical record.

 

test
Pineapple Code
Chattanooga Software Center • 1-423-821-3463 • 3821 Saint Elmo Avenue, Chattanooga, TN 37409 USA

Copyright © 2024 All Rights Reserved. Privacy, Terms, Glossary and Staff