There are many resources offered in order to learn to play bridge.
ACBL Online Intro to Bridge Classes -- online introduction to bridge course offered by the ACBL
Free Trickstarter Bridge Class -- free online one-hour crash course about the basics of bridge offered by the ACBL
Bridge Base Online -- free online resource to play bridge, practice bidding and watch international events
Learn on Your Own - a variety of websites and books recommended for the new player
Bridgeclues.com - daily free bid and play problems