Complex sentence: GKS was fairly on computer workstations in the 1980s and early 1990s, and formed the basis of Digital Research's GSX and GEM products; the latter was common on the Atari ST and was occasionally seen on PCs particularly in conjunction with Ventura Publisher.
Split into simpler sentences: GKS was fairly common on computer workstations in the 1980s and early 1990s. GKS formed the basis of Digital Research's GSX and GEM products; the latter was common on the Atari ST and was occasionally seen on PCs particularly in conjunction with Ventura Publisher.