Hello can anyone explain to me the difference between SATA and Raid or are they one of the same?

I recently bought a DVD burner that has a SATA interface. I didn't have a SATA power connect on my mother board so i bought a PCI SATA card and it works really well.

I was planning to buy a secondary hard drive which also has a SATA interface but i was reading some reviews that some SATA cards may not be Raid can anyone help me on this. The PCI card has 2 two ports one which is in use for the DVD burner the other is free. The card is a Silicon Image card or something like that

 

Thanks for any info