 Circle theorems are like little puzzles. You use your new knowledge to solve interesting geometrical problems using logical thinking as you go. Or we can look at the theorems. There is some key terminology that we need to master first. Which parts of the circle can you label? Pause the video and have a think. How did you get on? I find it quite tricky to remember the difference between a sector and a segment. But just think of it as a sector or slight. Orange segments are definitions match up with which parts of the circle did you get on? Because we have to use those key words when describing the theorems.