Pepperoni is an Italian-American invention, not a traditional Italian sausage. It was created by Italian immigrants in the United States, specifically appearing first in Lower Manhattan, New York City, around 1919

. These immigrants adapted traditional Italian dry salami recipes by adding paprika and other chili pepper-based spices, which gave pepperoni its distinctive red color and spicy flavor

. Pepperoni is typically made from pork or a mixture of pork and beef, although turkey is sometimes used as a substitute in the U.S.

. The sausage is cured and air-dried, making it suitable for pizza toppings due to its flavor and preservation qualities

. In summary, pepperoni originated in early 20th-century America, developed by Italian immigrants using American ingredients and spices, and has since become a staple pizza topping in the U.S.