Wikipedia is a compendium of human knowledge, edited by anyone who cares to contribute. It has articles covering everything people might want to know about, including references to source material for further reading. Its goal is to become an authoritative encyclopedia.
Wikipedia (free)
Wikipedia is a compendium of human knowledge, edited by anyone who cares to contribute. It has articles covering everything people might want to know about, including references to source material for further reading. Its goal is to become an authoritative encyclopedia.