Learn X in Y Minutes
learnxinyminutes.com
A community-written cheat sheet site covering 170+ programming languages and tools in a dense, example-heavy format — showing syntax and idioms from variable declaration to classes in a single scrollable page.
Why it is useful
The fastest way to get productive in an unfamiliar language when you already know how to program. Instead of a tutorial that builds from basics, it shows you the important parts all at once: variable declaration, control flow, functions, classes, and idiomatic patterns. The density that makes it bad for beginners makes it excellent for experienced developers picking up a second or third language.