At first, the term context is used a lot, but even if you have prior knowledge and say you will explain it later, I think it would be better to just briefly touch on it at the beginning. It appears constantly from the beginning to the middle of the lecture, but it is frustrating that you just pass it over saying you will explain it later. Of course, you can Google it and find out for yourself, but I am leaving a few words here for students who cannot.