What are the small circles next to an item that you check called?

Answer 1

on computer forms on web pages you will find

1. Check boxes, usually square. You can check (tick) any number of them.

2. radio buttons. usually circular, sometimes diamond shaped. If you choose one in a group, any previously selected one becomes unselected. They are named after the bandswitching buttons on old radios, which worked similarly to the station select buttons on modern radios. If you select one, the others cancel.