The Apple III was announced on May 19, 1980, during the National Computer Conference in Anaheim, California. In the fall of 1980, Apple ships the first Apple III units in limited quantity. It runs twice as fast as the Apple II and has twice as much memory - 128k of RAM. It is also the first Apple computer to have a built-in floppy drive, a Shugart 143k 5.25-inch floppy drive. The Apple III has 4 internal expansion slots that are compatible with Apple II cards, and also has Apple II Plus emulation built-in. The Apple III chassis is a single, heavy piece of aluminum, with the power supply totally enclosed in the left section, with no ventilation what-so-ever. On April 24, 1984, the entire Apple III line was retired with only 65,000 units sold in total. The Apple III Plus was on the market for a total of 4 months! Tested and working.