It is a chain. Delta Pizza originated in Italy, is an international chain of pizzerias, initially established in Italy in the 1960s, and then rapidly developed and expanded, and now has thousands of outlets around the world, including the United States, the United Kingdom, Canada, Australia and other countries. Delta Pizza, headquartered in Ann Arbor, Michigan, USA, was founded by Tom Monaghan, with Patrick Doyle as the Chief Administrative Officer. Delta Pizza entered the Chinese market in 1997, and by mid-April 2022, it already had more than 140 stores in Shanghai, over 120 stores in Beijing, and even more stores in Hangzhou, Tianjin, Suzhou, Nanjing, Shenzhen, Guangzhou, Wuxi, Ningbo, Dongguan and many other stores, the country has more than 480 stores.