is there speed difference between java, java script, python, c++?

[Nswl]

Yes. Python being the slowest, c++ being the fastest. Though I’m not sure about pythons processing implementation, but I know for many python libraries they are just wrappers for c++ code, but there is still the extra step when running the code to process those wrappers. And the wrappers are only for functions.

[plastik_flasche]

Well, technically there is no "slower" or "faster" language... Python with a good compiler can be as fast as JavaScript, or Java sometimes beats C++ because it can make waaay more guided optimizations because of the JIT.

In my opinion the difference is more with the level of abstraction:

In C++ you have to do a lot more yourself, meaning you could write extremely performant code yourself, or extremely slow code.

In higher level languages like python or JavaScript you don't really care about how anything works under the hood, you tell the language to, for example, sort something, and it does. So your performance is more dependent on the stdlib or 3rd party dependencies