The Rat Terrier comes to us from Great Britain where they were bred by crossing Smooth Rat Terriers and Manchester Terriers.  The original coat color for the Rat Terrier was black and tan.  When these dogs were brought into the United States in the 1890's breeders here re-crossed them with Beagles, Whippets and even Italian Greyhounds to result in the coat colors commonly found today (tri color) and certain personality traits, such as speed, agility,and hunting ability,  which were felt useful for a dog used mainly for ridding farms of vermin, especially rats.  The Rat Terrier's coat today is always a short single layered coat, which doesn't require much care.  The occasional brushing will remove dead hair and keep the coat in optimal condition.  Rat Terriers make fine companion pets, sensitive to their owner's mood, eager to please and easy to train.  They do require a good amount of exercise, so daily walks are recommended if a good sized yard is not available.  Rat terriers are good with children and usually friendly even with strangers.  This is an extremely hardy dog that adapts well to changes in environment and new activities, so they should be easy to integrate into your family's everyday life. One word to the wise:  Rat Terriers like to dig and may be able to dig out of an outside enclosure if you do not prepare for this propensity.