The Standard Ten was a model name given to several small cars produced by the British Standard Motor Company between 1906 and 1961. The name was a reference to the car's fiscal horsepower, a function of the surface area of the pistons. This system quickly became obsolete as an estimate of the power produced by the engine, but it continued to be relevant as a way to classify cars for tax purposes. Like other manufacturers, Standard continued to use the name to define the approximate size of their 'Ten' model long after the origins of the name had, in Britain, become inapplicable.
An experimental two-cylinder 10 hp was made in 1906, after which Standard's next car in that category was a four-cylinder 9.5 hp built between 1914 and 1919. They returned to the 10 hp market in 1934; this model was replaced by a "Flying Ten" in 1937 that lasted until the outbreak of World War II.
Standard returned to the 10 hp market in 1954 with another Ten, which was supplemented in 1957 by an up-market version called the Pennant. The Ten and the Pennant were replaced by the Triumph Herald in 1961.