CassettesCassettesCassettes were introduced in the 1960’s and gave other tape formats some competition. They were inexpensive, compact and most important, portable. The first cassettes could hold 90-minutes, but by the 1970’s the format could hold 2 hours of audio. Unfortunately, the quality of a recording on magnetic tape goes down over time. The tape is also prone to break. Cassettes were nearly wiped out in the 1980’s when the digital CD was introduced. However, cassettes are still available.