In the 1980's, computer software was sold in catalogs and magazines. Users had either of three platforms: A Macintosh, a PC-Compatible (probably x86), or a Comm

In the 1980's, computer software was sold in catalogs and magazines. Users had either of three platforms: A Macintosh, a PC-Compatible (probably x86), or a Commodore/Amiga. So these are the three categories were there to help you order the correct version of oregon trail. They were really a name for the operating systems, not the specifics of the hardware, at least back then they were.