Tim Drake, the current Robin, is 
technically the second Robin in the series.
In actuality, he was the third Robin, but the
series didn't want to show the death of Robin.
So instead, they give Tim partial background.

Tim Drake was a juvinal delinquent.  He took 
things out with his father, until his father was
killed by Two-Face; who he calls "puke face".  
Out for revenge, he went out to kills Two-Face, 
but instead found a new life ahead of him.  

When Batman took him back to the batcave, he found
his way upstairs, where he found the identity of 
Batman.  Pleading with Batman, he begged if he 
could help Batman.  Batman refused, and Tim decided
to go along anyway.  

Now, we see Robin in nearly every episode.  He has
a smart mouth along with the skills.  He still has 
a lot to learn, and he awaits what comes ahead of him.