There are two main types of pizza cutters. The most common uses a wheel that rotates in a circle while a person moves the cutter in a direction that they would like to cut the pizza. The other type is a large curved knife called a mezzaluna, which is rocked back and forth to cut the pizza. These two types of pizza cutters come in many different sizes. Many people might use the wheel pizza cutter for other things, including craft work. Some types of mezzalunas are often used to mince herbs or chop vegetables.