BBY/ABY is used to position items along the Star Wars Timeline. BBY refers to Before the Battle of Yavin. ABY refers to After the Battle of Yavin. The Battle of Yavin in Episode IV: A New Hope occured in 0 BBY/ABY.
One of the most fearsome enemies of the Galactic Republic, General Grievous, has made it his sole duty to hunt down and destroy every last Jedi. In this trilogy of stories, a group of young clone soldiers goes up against Grievous's droid army, the general captures R2-D2, and finally the Jedi find themselves trapped inside Grievous's evil lair. Be careful, you never know what will happen when Grievous Attacks!