I really love  whittling, it's the art of carving shapes out of raw wood using a knife.
Oh fascinating, I have heard of it but dont really know much about it, What kind of things do you make? 
I usually just make little action figurines, I use a light small-bladed knife, like a pocket knife.
Thats really cool, Id like to make some tiny action figured myself, How many years of practice did it take you?
About 5 years, some people also just repeatedly shave slivers of wood over and over again in a non-artistic way, that's also called whittling too.
Oh ok I suppose thats a good way to practice, Does it take a special kind of knife? or can I whittle with just any old knife? 
If you want to sculpt artistic work, it's preferred to use specialized whittling knifes with fixed single blades, but you don't have to of course.