Definition: data set

(1) For the Commodore 64 tape cassette, see datasette.

(2) In earlier AT&T terminology, a data set was a telephone modem. See modem.

(3) A collection of related data. Originating in the mainframe community, the term data set is used as a generic description of a file or database, the latter often referring to multiple data sets (multiple tables) related in some manner, typically by name or account number.

In practice, the term data set is used very loosely. A data set, also spelled "dataset," may refer to a single file or collection of files and not necessarily to a true database system. See DBMS, database and file.