Computer Terminal Protocols

Why do terminal emulators still mess up their output when you resize the window? In this presentation, I walk through the history of UNIX terminals. I discuss:

• Antique methods of electrical communication, from Morse code to the famous barbed wire telephone network used by American farmers.
• A historical example of the difficulties of synchronous communication protocols.
• The use of punch cards as both a means of I/O logging (stock tickers) and as a means of programming (Jaquard looms => IBM 1401).
• The historical basis for a separate kernel TTY layer, and the ugly consequences.
• Finally: how communication asynchrony, punch cards, and the TTY system architecture cause the problems we know and love today.

Slides available here.