is there a difference between a heatsink and a cpu fan or are they the same exact thing?

The heatsink is the chunk of metal with fins that is pressed against the cpu, the fan is mounted on the heatsink to cool the heatsink after it absorbs the heat from the cpu. Usually a heatsink and fan are one unit.

k thx for clearing that up for me, im looking at the zalman 7700 and there is a copper and a copper+aluminum, what is the difference? considering the copper is 15-20$ more expensive?

I use the CNPS7000A-AlCu. The all copper one will have slightly better performance than the aluminum copper one. I don't know what processor you are using but one thing you have to look for, A Pentium specs allow for a maximum weight of around 400 grams. If you look at the specs you'll see the copper aluminum at just over 400, where as the copper one is around 700. That's close to a 1/2 pound over spec. If your computer is staying in one place there is no problem with the heavier all copper one. But if you are going to be moving it around a lot you are safer using the AlCu. Otherwise a sharp jar could rip the CPU socket right off the board. From what I've read there is only a degree or 2 difference between them. I'm running my P4 with an 18% overclock. My idle temps are 39C Idle and low to mid 50s at full load. Hope that helped you.