song titles on radio displayed?

okay,can someone please tell me what it is that the GM radios have,i saw an alpine with it,and the higher end in dash tvs have.it says the name of the fm song and station are displayed on the screen. i was working on a kenwood doube din that said the song that was playing.what is it that would tell me if the unit has it

It's called RDS (for the life of me I don't remember what it stands for) and most new GM radios have it as well as a few aftermarket ones. Just look for an RDS logo if you are interested in getting a radio that has it. Hope this helps.

--->Richard