People really need to learn that HTML & CSS are not programming languages. There's a difference between a markup language (hence the ML in HTML,) and a programming language.
But since everyone seems to be talking about both, I know HTML & CSS as well as C# and very little Python (with the latter being actual programming languages). I plan on learning full Python and maybe Ruby in the future, although I should probably get better at C# first.
Also, Flash isn't a programming language either. Flash is an IDE and ActionScript is the language.