Sbarro and UNO are two of the most popular pizzeria chains in the United States. Sbarro is an Italian-American fast-food restaurant chain that specializes in pizza, pasta, and other Italian dishes. It was founded in 1956 and has over 800 locations worldwide. UNO is a casual dining restaurant chain that specializes in deep-dish pizza. It was founded in 1943 and has over 140 locations in the United States. Both chains offer a variety of menu items, including pizza, pasta, salads, sandwiches, and desserts.