Commonplace Book

http://ryanholiday.net/how-and-why-to-keep-a-commonplace-book/

A commonplace book is a central resource or depository for ideas, quotes, anecdotes, observations and information you come across during your life and didactic pursuits.

I think having a system like the commonplace book is important. If you don’t record what you read, you’re likely to forget about it. Learning without execution is useless, but you can’t execute if you keep forgetting what you learn. My commonplace book project YCNotes.