A supermarket chain in the south and midwest U.S., Piggly Wiggly was founded in Memphis, Tennessee in 1916. Founder Clarence Saunders patented the idea of the self-service store with Piggly Wiggly.  It was the first to price mark items, have checkout stands and have refrigerated cases to keep produce fresh among other things. Piggly Wiggly's success inspired other supermarkets to adopt the self-service model in the '20s and '30s.