From wikipedia: A tabby is any cat that has a distinctive coat that features stripes, dots, lines or swirling patterns, usually together with a mark resembling an "M" on its forehead. Tabbies are sometimes erroneously assumed to be a cat breed. In fact, the tabby pattern is found in many breeds of cat, as well as among the general mixed-breed population.
http://en.wikipedia.org/wiki/Tabby_cat
