Ok, So i'm buying RAM (8GB) for my MBP. I have a 2010 15-inch with 2.4 GHz i5 processor. I don't know that much about RAM so what kind and brand do I need?
You can browse by Mac memory (look at Shop Catergory on the left side) and use the specs Hellhammer said DDR3 1066 SO-DIMM 1.5v 7-7-7-20 CAS Latency. You can also browse laptop memory, you might find better quality and price by doing so. The Mac memory is "guaranteed" to work however i would look for compatible "PC / Laptop" memory because the quality is actually better. Also, look at the ratings before buying anything.
P.S. I'm thinking of doing this. $50 bucks for 8GB of RAM is like a no brainer, especially if you actually do things on your comptuer besides facebook.
I'd try Amazon first, besides free shipping you probably won't have to pay sales tax for your state. This could end up being less expensive than Newegg for the same brand of RAM.