In Pictures: The Apple family tree

Apple III (1980 to 1984)

CPU class: 6502 OS: SOS, Apple Pascal Development status: Open Platform size: 2

The Apple III represented Apple’s first attempt to cater to the business PC market. As such, Apple intentionally hobbled compatibility with the earlier Apple II in order to differentiate it in price and market.

High price, limited third-party support, and a defective batch of early Apple III units led to tepid adoption of the Apple III and to its ultimate discontinuation in 1984. However, its flexible and well-received operating system (SOS, short for Sophisticated Operating System) served as the inspiration for ProDOS on the Apple II, which helped to extend that platform’s lifespan into the early 1990s.