JavaScript is one of the languages that wasn’t designed properly. In fact, it wasn’t designed at all. It was an afterthought that just slapped into the browser to have some kind of programming. And because Java was a hot subject at that time, it got Java in its name. It has absolutely no relation to Java, except for some syntax similarity and garbage collection.

There were a lot of attempts to make it better and it has become better but it still has all the fundamental issues that almost all script languages have – lack of type system and that makes it unusable to write anything big or complex.

In a language with the type system compiler knows the type