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(Superseded by the 1998 Version)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.)


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