What all does WWW (World Wide Web) comprise of?

I understand the difference between Inteet and WWW, that Inteet refers to whole network that binds all the machines (servers and clients or hosts) together and differentiates between each of them uniquely by their IP addresses whereas,
WWW refers to "The World Wide Web (WWW) is an information space where documents and other web resources are identified by URLs, interlinked by hypertext links, and can be accessed via the Inteet."

But then what else is left that doesn't come under WWW. Everything is accessed via url's, be it web pages(http), mails(smtp), files(ftp), etc and all this comes under web.
So what is it that WWW doesn't consist of ?

Also, why url's such as https://www.google.com consist of both http (protocol) and www (web)?
Kindly help.

Recent Questions...