Tortoiseshell describes a coat, not a breed. The coat blends black-based and orange-based colors in patches or a fine mottle, usually with little or no white. Dilute torties show soft gray and cream, and torbies add tabby stripes. Because the orange gene sits on the X chromosome, nearly all tortoiseshells are female.
Most torties adopters meet are domestic shorthairs, though the pattern also appears in Persians, Maine Coons and British Shorthairs. Their reputation for "tortitude" is mostly folklore. A cat's age, history and socialization say far more about personality than color does, so expect everything from shy and quiet to bold and chatty. Shedding is moderate, and a weekly brushing is usually enough for a shorthair.