It is most certainly the same thing. The main ingrediant is Methylphenidate. From add.about.com/od/concerta/s, "Methylphenidate is the main ingredient in Ritalin, Concerta and Medadate. Find out side effects, drug interactions and precautions before you start taking this medication."
Commonly Used Names
Ritalin
Ritalin SR
PMS-Methylphenidate
Riphenidate
Concerta (Extended release)
Metadate
I hate to get personal with you here but if you did not even know that then you need to question every thing you think you know about this subject.