There are lots of really bad ways to remove an oil filter. Many people operate on the idea that they aren't going to re-use it anyway, so it's ok if the filter gets destroyed on the way out. Stabbing it with screwdrivers so it can be twisted out using them as handles is one of the worst I've seen. Besides being a generally ignorant move, it's so unnecessary!
Oil filter wrenches come in either exact fit or belt/strap styles. The exact fit wrench is made for your car's filter and fits on the end like a socket. The belt or strap style operates by sliding a ring (rubber for belt style or metal for strap style) over the filter to grip it so you can loosen the filter with the handle. They are very handy to have around for home oil changes, and you can pick one up cheap. On most cars, the strap style will work great. If you have a hard to reach filter, you might be better to go the exact fit route. This way you can use a ratchet wrench and an extension to get in there.
Check out a picture of an oil filter wrench.
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