A cassette is a form of magnetic storage media that was used for programs by home computers that were used in the late 1970s and early 1980s. They were originally designed for recording and playing back audio, but computer companies eventually manufactured cassettes designed for storing program data. Cassettes required the use of a cassette drive, either with a standard cassette player hooked up to the computer or with a specialized cassette drive by the computer's manufacturer. They were rather slow in both loading and saving programs.
Coleco developed a special kind of cassette drive for the Coleco Adam called the "data pack drive" which used special cassettes on a drive that was much faster than standard cassette drives, yet was slower than a floppy disk drive.