Formatted File System

The Formatted File System (FFS) is the name of a series of Database Management Systems (DBMS) developed for military use and designed to run on IBM mainframe computers.

The period from 1964 to 1968 saw the transition from isolated DBMS development efforts to the development of DBMS families. The Formatted File System is one such family. Others included General Electric's IDS family, and the Mark IV series developed by Informatics Inc. (later acquired by Sterling Software). These families were developed across organizations and branches of government, spreading and evolving with their primary developers. Beginning around 1968, industry DBMS development became increasingly proprietary.

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