What species is Yoda, and where is he from?

No one knows the answers to these questions except perhaps George Lucas himself. He has intentionally left out this information, and it probably will never be revealed, because Lucasfilm prefers to keep it a mystery. If you've heard that Yoda's species is called a "Whill" and that he is from the planet "Grentarik" (or that his last name is "D'Kana"), this is incorrect. This is fake information made up by SuperShadow.