On the original IBM Personal Computer, and the IBM PCjr, an interface was provided to allow the use of a compact cassette tape recorder to load and save data and programs. It was common for users of home computer of the time, such as the Apple II, Commodore 64 and BBC Micro, to save use cassette tape for storage if they could not afford a floppy disk drive, and in many cases there was a wide range of commercial software available on tape. This however was not the case with the IBM PC - very few were shipped without at least one floppy disk drive, and apart from one diagnostic tape available from IBM, there seems never to have been software sold on tape. An IBM PC with just an external cassette recorder for storage could only use the built-in ROM BASIC as their operating system, which suppo