In an interesting post on Inverse, [Sarah Wells] does a deep dive into something you probably don’t think about very often: the blinking cursor. You’d assume there wasn’t much to the story.

The text cursor is a vertical line (|). Also called a "caret," "i-cursor" or "I-beam," it may or may not blink. If the cursor is an arrow or hand, the text cannot be highlighted or changed.

Click your mouse or trackpad, and the eyes blink. It's fun and useful. That's all there really is to it. If you're bored on your Mac, you can bring your cursor up to the googly eyes to mess with ...

where my cursor will predictably reappear. Click your mouse or trackpad, and the eyes blink. It's fun and useful. What do you think so far? Post a comment. That's all there really is to it.

I/D: Increments (I/D = 1) or Decrements (I/D = 0) the DD RAM address by 1 when a character code is written into or read from the DD RAM. The cursor or blink moves to the right when incremented by 1 ...