Rex (thing)

This is the genealogy of the programming language Rex:

Rex was born in year 1979.
It became Rex 2.00 in year 1980.
It became Rex 3.00 in year 1982.
It became Rexx 3.20 in year 1984.
Then it begat NetRexx in year 1991.
It became Object Rexx in year 1997, and has not changed much since that time.

This genealogy is brought to you by the Programming Languages Genealogy Project.