Pretty much anything. I use it to learn foreign alphabets and languages, historical people and events, philosophical terms, computer networking concepts, outdoo

Pretty much anything. I use it to learn foreign alphabets and languages, historical people and events, philosophical terms, computer networking concepts, outdoor survival tips, and a bunch of other things. The best sources of information are encyclopedias (traditional ones, not Wikipedia) and dictionaries, as they are written to summarize a concept in a few hundred words.