What does ABY and BBY mean?
These are abbreviations for After the Battle of Yavin (ABY) and Before the Battle of Yavin (BBY), the Battle of Yavin being the events witnessed in the first Star Wars film made, i.e. Star Wars Episode IV: A New Hope and the destruction of the Death Star. All events within the Star Wars universe are described as occurring either before or after the Battle of Yavin. Other variants of these abbreviations include ASW4 and BSW4 meaning After Star Wars [Episode] 4 and Before Star Wars [Episode] 4. For clarity, and where possible, Star Wars Books does abbreviations.