Okay kiddo, let me tell you about pizza cheese!
You know how pizza has that yummy, stretchy cheese on top? Well, that cheese is called "mozzarella cheese".
Mozzarella cheese is made from the milk of cows, sheep, or water buffalo. First, the milk is heated up and mixed with some special bacteria called "starter cultures" that help turn the milk into cheese. Then, an enzyme called "rennet" is added to the milk, which makes it thicken and turn into curds. These curds are then mixed and stretched until they become long, thin strings - that's the stretchy part you love about pizza cheese!
Now, some people like to put other types of cheese on their pizza as well, like cheddar, Parmesan, or provolone. These cheeses are also made from milk and go through a similar process of heating up, adding starter cultures and rennet, and then being aged and flavored.
So there you have it, pizza cheese is made from milk and goes through a special process to become stretchy and delicious!