Online Backgammon
The basic backgammon rules are quite simple. You roll two dice and move your checkers the number of steps shown, one checker for each die or the same checker for both dice.
The goal is to move all checkers around the board, bring them into your home board and bear them off the edge.
If you roll two identical dice, let's say two threes, it's the same as if you had rolled four threes. You can combine the threes any way you like and move one checker 12 steps or two checkers six steps each, or one checker six steps and two checkers three steps each, etc.
Jumping over blocks
If the opponent has two or more checkers on the same field (a block), your checker cannot land on that field. You must land once for each die and cannot add the dice to bypass a block.
On the contrary, if the opponent has a single checker on a field (a blot), you can land on that field. In this case, your opponent's checker is hit and must be moved to the bar (in the middle of the board.)
Hitting blots and re-entering from the bar
This is good for you, since before your opponent is allowed to move any other checkers, he must re-enter all checkers from the bar. These checkers re-enters in your home board, starting from field 1. That is, they must move all the way around the board again.
Bearing off your checkers
Once all your checkers are gathered in your home board, you can start bearing them off over the edge. For each die you roll, you must use all its pips if you can. To use a 3, you cannot bear off a checker that has only two steps left - except if there's no checkers left further away.
The player who first bears off all checkers have won. It's as simple as that. Or, as you'll notice, it's not that simple at all!
The most important tips for beginning backgammon players are probably: Move quickly around the board, avoid leaving blots, hit your opponent's blots, and try to close in the opponent's checkers behind consecutive blocks (a prime),
A great way of learning is to play backgammon online against other players at your level. There are some really good sites with lots and lots of players on all levels. Try it out!