You are not talking about knowledge. Knowledge is independent of its representation. You are talking about information. Information is a particular representation of knowledge.

Creating a website that contains the sum of human knowledge would be almost legal. There are a few things that are forbidden, but you can get away with a lot provided that it is unbiased. Creating a website that copies information (i.e. the bits) from one place to another is frequently illegal, even when the author offered up that information free of charge.