# Wiki on Math and Science

People always ask me why I take notes. I tell them, if you become a professor, you must teach subjects. If you write notes as you wrestle with a subject, you remember what you had difficulty with as you learned it. I tend to forget what was difficult or easy after I learned, or else I forget the whole subject.

So my notes take the form of 1-page “executive summaries” of subjects. That way, if you come to me and say “Teach me everything you know about X in ten minutes”, I can tell you “Give me three minutes to review” and examine the relevant summaries.

It turns out, the one-page summaries are good if they can be used as the basis for exercises.