To really understand how ed was useful, it's eye-opening to see exactly what life was like before video terminals.
Essentially, think of using your laptop, but instead of looking at a monitor you're reading the output from a printer. So if you type `ls`, you see the directory listing being literally printed out on a dot-matrix printer. Naturally the only way of text editing is with a line EDitor, which lets you edit text one command at a time.
When trying to use ed on a video terminal, it obviously looks wasteful. But that's because it was designed before video terminals were a thing. Kind of like using a modern day graphics card to play pong.
Wow, that is a fascinating video and such an inspiring spirit of hacking. I'd love to learn more about the electrical engineering side of computer science to be able to do similar experiments.
Essentially, think of using your laptop, but instead of looking at a monitor you're reading the output from a printer. So if you type `ls`, you see the directory listing being literally printed out on a dot-matrix printer. Naturally the only way of text editing is with a line EDitor, which lets you edit text one command at a time.
When trying to use ed on a video terminal, it obviously looks wasteful. But that's because it was designed before video terminals were a thing. Kind of like using a modern day graphics card to play pong.
here is a video illustrating using a teletype:
https://www.youtube.com/watch?v=2XLZ4Z8LpEE