1991 ACM Computing Classification System

Valid through 1997

(Superseded by the 1998 Version)

The full ACM classification scheme involves three concepts (described more fully in the Introduction): general terms, implicit subject descriptors, and the four-level tree (containing three numbered levels and a fourth unnumbered level).

General Terms

These apply to any elements of the tree that are relevant.

  • Algorithms
  • Design
  • Documentation
  • Economics
  • Experimentation
  • Human factors
  • Languages
  • Legal aspects
  • Management
  • Measurement
  • Performance
  • Reliability
  • Security
  • Standardization
  • Theory
  • Verification

Implicit Subject Descriptors

Names of languages of systems may be used under appropriate nodes, e.g., Pascal under D.3.2 (Language Classifications) or VM under D.4.0 (Operating Systems -- General).

Top Two Levels of the ACM Computing Classification System (1991)

Full Tree with Subject Descriptors

The full ACM classification tree is available as a hypertext document, as a single document, or as an ascii file. (An asterisk (*) next to a subject descriptor indicates that the classification is no longer be used as of January 1991, but that the item is still searchable for previously classified documents.)

Copyright 1997 by Association for Computing Machinery, Inc. (ACM). Permission to make digital or hard copies of part or all of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage, the copyright notice, the title of publication and its date appear, and notice is given that copying is by permission of ACM, Inc. To copy otherwise, to republish, to post on servers, to implement in search and retrieval software, or to redistribute to lists, requires prior specific permission and/or a fee. Request permission to republish from:

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MAC / 95-Nov-8 
Tom Horton / 96-July-16