The Cairn is the essence of terriers. It is named after the Scottish cairns, heaps of stone used as memorials or landmarks. This small-sized breed could squeeze itself into the cairns to exterminate rats and other small wild animals. It is plucky, spirited, bold, inquisitive, hardy, clever, stubborn, and scrappy. The best-known cairn may be Toto in the Wizard of Oz. Affectionate, its devotion to its owner sometimes borders on jealousy.