Want to learn a new programming language. My main language is JavaScript and I spent most of my team learning to create full stack applications with it, but I would like to learn a second language to focus on. (I already have some experience in Java and Python and JavaScript wasn't my first language but I like JS)

Are there any languages that you could suggest me?

You can try to learn a low-level language such as c or even assembly if you are brave.
It can be quite refreshing if you haven't tried it before.

Just my 2 satoshis.

Leverage your javascript with typescript

@Tamirse that would be pretty interesting. I guess by learning them I would learn a lot about how a computer actually works.
I will think about it.

@searchindex I would like to learn something unrelated to js, but I might learn typescript in the future

Thank you all for your comments. I think I will go with C++ . I think that learning that will teach me a lot

I'd say it really depends on what you want to do with it (what platforms you want to code for), or is it purely for educational purposes?

Python would be an easy next step, being another dynamic language.

But if you want more of a challenge and you have any interest in coding for iOS I would suggest either Swift or Objective-C.

I kind of hate Swift, but it's probably a little more comfortable to learn than Objective-C, but Obj-C is a really killer language and much better than Swift in many ways (namely power).

JavaScript and Objective-C are two of my all-time fave languages.

JavaScript is my favourite language, but I would recommend Go as your second lang.

Try something different. I would recommend you give lisp a try. It forces you to think differently. After you do lisp, you will have an easy time picking up Erlang or Elixir.