Today in 1991, Sony’s President Norio Ohga announced the MiniDisc as the new personal audio format. From Sony’s official history: “Ohga had led the establishment of the CD business, and CD technology had quickly replaced analog audio technology thanks to its digitally-based, high speed random access and direct search capabilities. CDs were a great success, but they were originally a read-only media, and Ohga wanted to make something that was rewritable, a kind of disc that would replace the audio compact cassette….To enhance portability, the disc was housed in a shell. The MD combined recordable features of the cassette tape with the random access functions and high quality sound of the CD. Sony clearly explained the difference between the CD and MD; the CD was for leisure listening and the MD for enjoying music anywhere and anytime, much like the Walkman.”

Wikipedia: “The biggest competition for MiniDisc came from the emergence of MP3 players. With the Diamond Rio player in 1998, the mass market began to eschew physical media in favor of file-based systems, rendering cassette- and disc-based formats obsolete by the end of the 2000s.”