Pizza is a traditional Italian dish
What are traditional toppings placed on the pizza?
There are many types.   It can also be topped with additional vegetables, meats, and condiments,
When was pizza first introduced to the United States?
by emigrants from there. This changed after World War II, when Allied troops stationed in Italy came to enjoy pizza along with other Italian foods.
Origins.
Foods similar to pizza have been made since the neolithic age. Records of people adding other ingredients to bread to make it more flavorful can be found throughout ancient history.
- In Sardinia, French and Italian archaeologists have found bread baked over 7,000 years ago. According to Professor Philippe Marinval, the local islanders leavened this bread.
- In the 6th
the rolled pizza dough is folded in two over the stuffing and the edges are sealed before the dish is fried.
Regional variations In the United States.
In the United States, calzones are typically made from pizza dough and stuffed with meats, cheeses and vegetables. 
Traditional calzone dough, consisting of flour, yeast, olive oil, water and salt, is kneaded and rolled into medium-sized disks.
Each is then filled with cheeses such as ricotta, mozzarella, Parmesan, provolone, and other traditional vegetables