Windows 7: How many types of heatsinks are there according to socket type?

I will buy a new motherboard and i don't know if the heatsink from my PC would fit on it

Look at the specs of the new motherboard - the socket type will be listed. Look at the specs of your current heatsink - the socket type will be listed. If they match, it will fit. Now, if you replace the processor, you will have to verify that your current heatsink is recommended for the new processor.

What do you mean by "recommended"? if they have the same socket type or in other way?

Tell us what motherboard and processor you are going to get. Also which chassis you will be putting the board in so we can make sure that any recommended coolers will fit inside the case with the side panel on.

example, socket 1155 and 775 don't have compatable heat sinks the locking pin placement is slightly different basicly the 1155 is a larger square area.

you can't physically use a different socket heat sink.

if you bought a new motherboard and cpu together then you should have a heatsink provided, if you bought a new motherboard for your existing cpu then the heatsink will fit anyway assuming you bought the right motherboard for your cpu.

Just because a heatsink works on a certain socket does not mean that it is recommended for a certain type of processor. For example, there are several types of heatsinks for Xeon processors, and not all of them are interchangeable - some Xeons run cooler than others, so one type of heatsink may not provide adequate cooling for the processor. The heatsink manufacturer will provide that information for you.

Aftermarket heatsink/fan systems sometimes have adapters which permit them to be used for a variety of CPUs.

OEM HSFs tend to be specific to a socket type. I believe that Intel Socket 1155 and Socket 1156 HSFs are interchangeable, but few others are.

What do you have? What do you wish to buy?