What is a blocking function?

Question

What is a blocking function or a blocking call?

This is a term I see again and again when referring to Node.js or realtime processing languages.

Answer 1

A blocking call is one that doesn't allow processing to continue until it returns to the calling thread - this is also referred to as a synchronous call. Asynchronous on the other hand means that threads (and code) can execute at the same time (concurrently).