Coko (the Cooper-Kozdrowicki chess program) is a chess program written in FORTRAN. It plays a minimal chess game at the rate of 0.2 sec CPU time per move, with a level close to lower chess club play. It participated in four American computer chess championships (1970, 1971, 1972 and 1973). Later versions included the Mater software which is a dedicated piece of software to detect check-mate situations: both how to cause them and how to prevent them.
Schach is a chess program initially written in FORTRAN (version 1), later ported to ALGOL (version 2) and x86 assembly for DOS (version 3). Version 1 played in the American computer chess tournaments (1970, 1971 and 1972). Version 2 played in six World Computer Chess Championships between 1980 and 1986. Version 3 played multiple local European championships and international computer chess and microcomputer chess tournaments between 1991 and 1997.