SATA is Serial ATA. It's the newest form of interface from the hard drive to the system. It uses simpler data cables and different power cable to your hard drive.
It promises to be better and faster - but at present it's not really faster at all, and systems are not really ready for it - hence the number of problems when trying to set up SATA drives from scratch.
However it's bound to become the standard, because technology has to move forward, for better or worse.
At present IMHO, I would not use it. In a couple of years time, all new systems will probably use it as standard!