I think any beginner would love to have a [cross platform] offline browse-able reference/tutorial/guide whatever, be it MDN or W3Schools. Going to google for ev

I think any beginner would love to have a [cross platform] offline browse-able reference/tutorial/guide whatever, be it MDN or W3Schools. Going to google for every damn thing is just a waste of time. And, for people with little stacks, it usually deviates them making them forget what they were trying to do in the first place. I am talking about something like php.net's offline 'chm' file. But, for html, javascript and css. Does anything exist already?