Founded in 1965 as a mail order company for pet food and other pet supplies, in the intervening years, Petco has exploded into a national chain of more than 1,500 stores. Headquartered in San Diego, California, Petco offers thousands of pet-related products both in its retail stores and online at petco.com such as food, toys, medication, bedding and other essentials. Petco offers adoption services for cats and dogs in addition to the sale of small animals like fish and lizards. Petco.com has everything you need to keep your pets happy and healthy.