1980- Apple III
1980- The Apple /// was designed to be a business machine. It was partly compatible with the Apple II (thanks to a few options in the operating system). It used a powerful memory management system and worked under SOS (Sophisticated Operating System) which was a great, device -independent, operating system. This OS was the "ancestor" of ProDOS (the "professional" Apple operating system) and some parts of this system were used later in the Lisa and Macintosh OSs.
Despite its unique features, the Apple /// had a lot of technical problems, namely, the horrible case design. It caused the internal temperature to get so hot that the motherboard would warp and some of the socketed chips would become unseated. To remedy this, Apple told people to literally pick up the computer several centimeters off the desk and drop it! It was a miserable flop in the marketplace.
The Apple /// was followed in december 1983 by the Apple /// plus which had an Apple IIe style keyboard and a new video interface. Four months later, it was discontinued.
