Okay kiddo, have you ever seen a TV screen and how it shows pictures and words? Well, a long time ago, people didn't have computers to type on like we do now. They had to use something called a typewriter to write letters and documents.
But, there was a man named Don Lancaster who wanted to use his TV screen to do the same thing! He built something called a TV typewriter which could show letters and words on the TV screen just like a typewriter could on paper.
He did this by connecting the TV typewriter to his computer and sending code (which is like a special kind of message) to the TV. The TV could read the code and show the letters and words on the screen.
It was a really cool invention because it allowed people to type out things on their computer and see them on their TV screen. This was way back in the 1970s, so it was a big deal at the time. Nowadays, we have much fancier ways to type and display things on screens, but the TV typewriter was a very important first step in making that possible.