The number of slices in a 16-inch pizza can vary, but there are generally 12 slices in a pizza of this size as presented by a pizzeria. Alternative cutting methods, however, can produce anywhere between 17 and 24 slices.
Most pizzerias will accommodate requests for half slices, which is when standard slices are halved to create extra slices. A standard 12-slice 16-inch pizza would therefore produce 24 half slices. For those who find wedges awkward, some pizzerias will also accommodate requests to cut pizzas into squares or rectangles. Because square slices tend to be smaller, there are usually more square slices in a pizza than triangular ones.
Although it's one of the most popular foods in the United States today, pizza did not make its debut in the United States until the early part of the 20th century. Lombardi's in New York opened in 1905, and it claims to be the oldest pizzeria in the United States. Pizza didn't become a hugely popular dish in the United States until after World War II when American soldiers returned to the United States and brought with them popular dishes they had tried while serving in Europe. By 1957, frozen pizzas had made their way into supermarkets and homes throughout the country.