[pan69]

> So JavaScript meant "complement to Java

The whole JavaScript thing was just marketing. In 1995, Java was THE hottest thing so associating it with Java might fuel adoption/acception.

There is an old saying; Java is to JavaScript what Car is to to Carpet.

Re. your compiled question. It's up to the browser on how to execute JavaScript. E.g. Chrome has the V8 engine. This is the VM that compiles and executes JavaScript within Chrome. Other browsers might have different engines.

https://en.wikipedia.org/wiki/V8_(JavaScript_engine)