The MP3 player was invented in 1979

In 1981 Kramer filed for a UK patent for his newly conceived digital audio player, the IXI. UK patent 2115996 was issued in 1985, and U.S. Patent 4,667,088 was issued in 1987. The player was the size of a credit card with a small LCD screen and navigation and volume buttons and would have held data of at least 8 MB of solid-state bubble memory chip with a capacity of 3½ minutes' worth of audio... More here.

The forward looking abilities of Kramer are astonishing. See the video below for the strange and remarkable story.

https://www.youtube.com/watch?v=pSJi5YuK3gQ&t=210s