68Pxx Theory of data
- 68P01 General
- 68P05 Data structures (1)
- 68P10 Searching and sorting (1)
- 68P15 Database theory
- 68P20 Information storage and retrieval
- 68P25 Data encryption [See also 94A60, 81P94]
- 68P30 Coding and information theory (compaction, compression, models of communication, encoding schemes, etc.) [See also 94Axx]
- 68P99 None of the above, but in this section