Its just the internet is very unreliable, anyone can add their opinions. How do you know what is right and what is wrong? There is a reason books are still used, a bunch of scientists can publish a book and it can be verified and used as an official tool in education. You can't do that with the internet, it changes all the time and is filled with false facts.
Edit: Something like this: A Physics Book. It may not be free, but you will end up with a better understanding of physics than browsing the internet could give you.