Which Programming Language to Learn?

So I have been programming for 7+ years mainly in c#, obj-c, HTML, CSS and java(ew java...)

I really want to learn a new language but am not sure what to choose?

I was thinking maybe Javascript but am not sure, can anyone give any recommendations?

Thanks

What I do when I want to learn a language is I find something that I'm currently using that badly needs a re-write, then I start looking at various languages that might suit the purpose.

 

I'm currently learning Nim, which has some good validation when working with multiple threads, it *should* (I haven't actually tried it yet myself) ensure that there won't be any locking issues, at compile time. additionally when writing modules you can also write the test into the same file, which in my opinion can be handy, at least for my project.

Well if you know HTML and CSS, JavaScript would be beneficial to know and easy to get into. Especially considering your programming background.

I would do c++ because c++ is good.