What Does 'To Hang Out' Mean?

The term 'hang out' is used in the informal way when you are spending a lot of time in a particular place. You might have heard the word in the terminology of young people who spend a lot of time somewhere discussing something or sometimes doing nothing.
    
The word has its relevance in the context of the modern era because theses days we hardly find people spending time without any purpose and they are forgetting the relevance of the term. Because in common man's terminology, it is a waste of time but in reality it is serving a purpose; it is giving our brain to stray around myriad of topics and it is these myriad of topics that give birth to a new idea that can be relevant to the humanity.