8-track tape cartridge
Developed in the mid-1960s, the 8-track was the first commercially viable audio tape cartridge, and although it was a popular component of home stereo systems the real breakthrough was its suitability for cars. The tapes played on a loop, but you couldn’t rewind or fast-forward; you could only skip to the next “program,” of which the tapes had four. By the end of the 1970s they were replaced by smaller, rewind-friendly cassettes.
