RAM is a major importance in speed of your computer. RAM can vary in cost. One way to NOT  be CHEATED on the COST of RAM is too NOT BUY RAM OFF APPLE.COM. i just ordered a new macbook off there and I new what to do and what NOT to do. I went to the store and got 2GB of RAM for about $75 which is a fair price. On apple.com it costs $150 for 2GB and $850 for 4GB so I just chose the store. When choosing RAM, be sure to ask your retailer what type of RAM you should get for your specific computer. Computer vary in all sorts for RAM. This is a major part cause otherwise the RAM will be no use. Check your local stores for more info.