Your question contains a mix of English and Indonesian, and...

Your question contains a mix of English and Indonesian, and it seems you provided a phrase, not code. The phrase "Apa itu java" translates to "What is Java?" in English.

This isn't actual code, so there’s no functionality to describe. However, if you're asking about Java as a programming language, it is a versatile, object-oriented language designed for building applications that run on a variety of platforms.

If you have actual code, feel free to provide it, and I can help explain what it does!