Although initially termed 'Landships' by the Landship Committee, production vehicles were named 'tanks', to preserve secrecy. The prototype of a new design that became the Mark I tank was demonstrated to the British Army on 2 February 1916. In Great Britain, an initial vehicle, nicknamed Little Willie, was constructed at William Foster & Co., during August and September 1915.

Research took place in both Great Britain and France, with Germany only belatedly following the Allies' lead.

Although vehicles that incorporated the basic principles of the tank (armour, firepower, and all-terrain mobility) had been projected in the decade or so before the War, it was the alarmingly heavy casualties of the start of its trench warfare that stimulated development. The development of tanks in World War I was a response to the stalemate that developed on the Western Front.

A British Mark V* tank- carries an unditching beam on the roof that could be attached to the tracks and used to free itself from muddy trenches and shell craters A British tank destroyed by the Germans on the Western Front, 1917

First battle tanks were used