The Atari ST is a line of home computers from Atari Corporation and the successor to the Atari 8-bit family. The initial ST model, the 520ST, saw limited release in April–June 1985 and was widely available in July. The Atari ST is the first personal computer to come with a bit-mapped colour GUI, using a version of Digital Research’s GEM released in February 1985. The 1040ST, released in 1986, is the first personal computer to ship with a megabyte of RAM in the base configuration and also the first with a cost-per-kilobyte of less than US$1.
The Atari ST is part of a mid-1980s generation of home computers that have 16 or 32-bit processors, 256 KB or more of RAM, and mouse-controlled graphical user interfaces. This generation includes the Macintosh, Commodore Amiga, Apple IIGS, and, in certain markets, the Acorn Archimedes. “ST” officially stands for “Sixteen/Thirty-two”, which refers to the Motorola 68000’s 16-bit external bus and 32-bit internals.
You can browse and download most available games for free below, but you will need an emulator also to play them. For Atari ST we recommend https://hatari.tuxfamily.org/ but you can use any emulator of your choice and even original hardware if you have the know how!