Complex sentence: Sam's Club is a chain of membership-only retail warehouse clubs owned and operated by Wal-Mart Stores, Inc., founded 1983 and named after the after Wal-Mart founder Sam Walton.
Split into simpler sentences: Sam's Club is a chain of membership-only retail warehouse clubs. Founded in 1983, it is owned and operated by Wal-Mart Stores, Inc., and is named after Wal-Mart founder Sam Walton.