Here are a variety of chess website that teach all elements of playing chess.
Chess.com (http://www.chess.com/)
Thinking Machine(http://www.turbulence.org/spotlight/thinking/chess.html)
Chessbase News (http://www.chessbase.com/)
Chess Kids Academy (http://www.chesskids.com/)
Chess Corner (http://www.chesscorner.com/tutorial/learn.htm)
50 Chess Games for Beginners (http://www.50chessgames.freeserve.co.uk/): animated chess tutorial website written by beginners for beginners
Chesskit.com (http://www.chesskit.com/)
