Ashley Bruhn
Mozzarella cheese is one of the most popular cheeses in the world, especially when it comes to topping a pizza. Most of the time, the stuff you can find at the grocery store, which is low moisture, will do the trick, but if you're trying to make an authentic Neapolitan pizza then you need to get your hands on some fresh mozzarella.
Most easily found in an Italian or gourmet market or cheese shop, fresh mozzarella will hopefully have been made that day and is usually sitting in a brine or is wrapped in tightly in plastic. It can come in different sizes of balls, from bocconcini (very small) to ovolini (egg-size) to one large ball, about the size of a large fist.
Fresh mozzarella can come from two sources: Cows' milk--fior di latte and water buffaloes' milk--mozzarella di bufala. There are subtle differences, but both produce a silky, soft cheese that helps make a perfect Neapolitan pie. Yum!