Raven is based off of a DC superhero by the same name. Her design comes from her look in the 2003 Teen Titans tv show. She has no secret identity on the show. She is a stoic girl from the parallel world of Azarath, who draws upon dark energy and psionic abilities. She can convert her physical body into her soul-self and carry or teleport herself and others over vast distances in form of a giant black raven.
Robin is based off the DC superhero of the same name. His design was inspired by The Super Friends tv show that ran from the 1970s to the 1980s. His secret identity is Dick Grayson. While he doesn't have super powers, he has a variety of Bat-Themed weaponry and fight skills. He also has a lot of fun catchphrases like Holy Astronomy or Holy Return From Oblivion. There is actually a wikipedia page dedicated to just his catchphrases.