Sainsbury's is a major UK supermarket chain founded in 1869. It is currently led by CEO Justin King and has over 150,000 employees. The document provides a history of Sainsbury's, including that it started as a small dairy store and was a pioneer in areas like women employees, self-brand products, and fair trade. It operates various store formats today including supermarkets, convenience stores, and online shopping. Sainsbury's focuses on fresh food, general merchandise, complementary channels and services, and new business opportunities to remain competitive in the UK grocery market.