Télétel, the French Internet of the 80s — How did it work?

I suppose, most readers would not believe me if I write that already in the 80s the internet-like system was already working in France. But it was really so.

Minitel 1 © Image by author

How was it possible? Let’s figure it out.

History

Computers became connected to the network many years ago (the TCP and FTP protocols, which are still…