It's a branch of mathematics which wouldn't be considered a single branch without the practical concerns of programming driving it. You have everything from com

It's a branch of mathematics which wouldn't be considered a single branch without the practical concerns of programming driving it. You have everything from computability, sure, but you also have queuing theory (networking), formal grammars (parsers, compilers), relational algebra (database queries), and whatever else I'm forgetting, all under one banner, because all of them are useful to the same practical field.