Batgirl is the name of several female counterparts to Batman. Betty Kane was first introduced as Bat-Girl, but it was Barbara Gordon, daughter of Commissioner Gordon, who became the iconic Batgirl, joining Batman and Robin to defend Gotham City.
After she was crippled by the Joker, Barbara forsook her Batgirl identity, becoming the information retrieval specialist, Oracle. She returned to the role in the New 52 event, after surgery cured her paralysis.
Others to have donned the Batgirl cowl are Cassandra Cain (aka Black Bat) and Stephanie Brown (aka Spoiler) who was also the fourth Robin. Other brief claimants were Helena Bartinelli (aka Huntress) and Charlie Gage-Radcliffe (aka Misfit).< LESS