Back in the “dark ages” each microcomputer (as they were called before IBM introduced the PC) had its own operating system and software. Most of what would run on one computer would need major alterations made in order to get it to run on a different computer. Many, but not all, of the different computers used a version of CP/M as the operating system and most programs were written in BASIC which at the time was interpreted rather than compiled and most computer users knew all about the technical aspects of their chosen system so (trans)porting programs from one system to a different one was possible, it just involved a lot of work.

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