1979: RadioShack TRS-80 Model II with Integral 8-inch Floppy Drive
Radio Shack announced the TRS-80 Model II in May 1979 and began shipping the $3450 computer in October 1979. This machine was considerably more expensive than the original TRS-80 owing to the integral 8-inch floppy drive and robust chassis. The eight inch floppy had actually been invented in 1971 by an IBM team under Alan Shugart for IBM's System/370 mainframe. In 1978, Alan Shugart, now at Shugart Associates, developed the 5.25-inch floppy disk, so the 8-inch floppy drive was essentially obsolete at the time the TRS-80 Model II was introduced. The 5.25-inch floppy became the most widespread standard of the 1980's, later being supplanted by the 3.5-inch floppy which appeared in the Apple Macintosh in 1984, the Amiga 1000 in 1985, and the IBM PS/2 in 1987. A smaller 2-inch floppy appeared later, but this size never achieved extensive use.