I drove around all day, parked my car and got in it to leave and nothing. I had to get a jump. Drove around some more parked it for about an hour and then it would not start again. Is it the battery or alternator?

It sounds like a classic case of a battery that will not hold or accept a charge. It could certainly be another issue as well, with the charging system for example. But in step-by-step testing, you'll need to check and verify your battery is not failing first. Once you have a verified, known good battery that can take a full charge and hold a load, then you can check the alternator amperage and voltage output reliably. www.repairpal.com/repair-shops There is a link to some shops near you to call upon. They'll be able to give you a definitive battery test, and most of them will do it at no charge.