Tortoiseshell describes a coat, not a breed. The pattern mixes black-based and orange-based colors in patches or a fine mottled blend, usually with little white. Add large white areas and the cat is called a calico. Dilute torties look soft gray and cream, and torbies add tabby stripes. Nearly all are female, because the orange gene sits on the X chromosome.
Most torties in Wilmington homes are domestic shorthairs, though the pattern also shows up in Maine Coons, Persians and many other breeds. Expect moderate shedding, a brushing once or twice a week, and a lifespan of roughly 12 to 18 years. The famous "tortitude" is closer to folklore than science, so a cat's age, history and socialization say more about personality than color does.