Digital Equipment Corporation (originally and commonly abbreviated as DEC, later formally abbreviated as Digital), headquartered in Maynard, MA, outside of Boston, was at one time the second-largest computer company after IBM. DEC itself was a spinoff of MIT's Lincoln Laboratories. During DEC's boom times, it was said that half of NESFA worked at DEC. Many fen moved to the Boston area to work for DEC.

Fans were deeply involved with the Incompatible Timesharing System written at MIT for the DEC PDP-10.

There are numerous references (mostly in instafilk page-filler songs?) to the DEC PDP-11 (see in the HOPSFA Hymnal, more about that family of machines here.

As the minicomputer was replaced by the PC, DEC's business suffered, resulting in DEC selling off some products, along with the employees who supported them, to other companies, and waves of layoffs. Eventually, DEC was purchased by Compaq which was in turn purchased by Hewlett Packard (HP). DEC is fondly remembered by ex-DECies, and some never really recovered from DEC's collapse.

See also here, The Boston Globe's timeline and photographs, and Gordon Bell's historical archives.

The Computer History Museum had its origin in The (Digital) Computer Museum which grew out of DEC's and Gordon Bell's private collections.