Industry: Retail
http://www.walmart.com/

Wal-Mart Stores is an irresistible (or at least unavoidable) retail force that has yet to meet any immovable objects. Bigger than Carrefour, Royal Ahold, and Kroger combined, it is the world's #1 retailer, with about 4,700 stores, including 2,900-plus discount stores (Wal-Mart), combination discount and grocery stores (Wal-Mart Supercenters and ASDA in the UK), and membership-only warehouse stores (SAM'S CLUB). Most of its stores are in the US, but Wal-Mart is expanding internationally; it is the #1 retailer in Canada and Mexico. Wal-Mart also has operations in South America, Asia, and Europe. Founder Sam Walton's heirs own about 38% of Wal-Mart.
source: Hoover's also see: Wetfeet.