Tall and lean, the Greyhound is the fastest breed of dog. As a sight hound, the breed pursues game using its vision and speed. Today, however, the Greyhound primarily serves as a sweet and personable companion. The breed can be any color, including black, fawn and red, often combined with white or brindle markings. The Greyhound has been owned by many prominent figures in history, including President Rutherford B. Hayes and General George A. Custer.