The Free On-line Dictionary of Computing (18 March 2015):
An interactive DBMS, originally
from Ashton-Tate Corporation, and the language used by it.
dBASE evolved from Vulcan by Wayne Ratliffe, which came out
in around 1980 and ran on CP/M. It was called dBaseII when
sold to Ashton-Tate Corporation.
The first release was dBASE II, ca 1980. There never was a
"dBASE I". Later versions included: dBASE III, dBASE III+,
and dBASE IV.
Ashton-Tate was taken over in the early 1990s by what became
Borland Software Corporation who sold dBase in March(?)
1999 to the newly formed dBase Inc. dBase Inc's first release
was Visual dBASE 5.7, a Y2K upgrade to Visual dBASE 5.x.
Current version, as of 2003-11-24: dBASE PLUS 2.0x build 1703.
dBase Home (http://dbase.com/).