I _totally_ recommend this week's episode of On the Media.

At least the first part:
In 1983, Simon Goodwin had a strange thought. Would it be possible to broadcast computer software over the radio? If so, could listeners record it off the air and onto a cassette tape? This experiment, and dozens of others in the early 80s, created a series of cassette fueled, analog internets.

https://www.wnycstudios.org/podcasts/otm/episodes/on-the-media-how-cassettes-changed-the-world