Driver was a military rank

Military rank

Military rank is a system of hierarchical relationships in armed forces or civil institutions organized along military lines. Usually, uniforms denote the bearer's rank by particular insignia affixed to the uniforms...

 used in the British Army

British Army

The British Army is the land warfare branch of Her Majesty's Armed Forces in the United Kingdom. It came into being with the unification of the Kingdom of England and Scotland into the Kingdom of Great Britain in 1707. The new British Army incorporated Regiments that had already existed in England...

 and the armies of other Commonwealth

Commonwealth of Nations

The Commonwealth of Nations, normally referred to as the Commonwealth and formerly known as the British Commonwealth, is an intergovernmental organisation of fifty-four independent member states...

 countries. It was equivalent to the rank of Private

Private (rank)

A Private is a soldier of the lowest military rank .In modern military parlance, 'Private' is shortened to 'Pte' in the United Kingdom and other Commonwealth countries and to 'Pvt.' in the United States.Notably both Sir Fitzroy MacLean and Enoch Powell are examples of, rare, rapid career...

.

The rank was initially used in the Royal Artillery

Royal Artillery

The Royal Regiment of Artillery, commonly referred to as the Royal Artillery , is the artillery arm of the British Army. Despite its name, it comprises a number of regiments.-History:...

 for the men who drove the teams of horses which pulled the guns. It was phased out after the First World War (when all Royal Artillerymen of the lowest rank were redesignated as Gunners

Gunner (rank)

Gunner is a rank equivalent to Private in the British Army Royal Artillery and the artillery corps of other Commonwealth armies. The next highest rank is usually Lance-Bombardier, although in the Royal Canadian Artillery it is Bombardier....

). It was also used in the Royal Australian Artillery and Royal Canadian Artillery.

It was also used by all the Private-equivalents of the Royal Army Service Corps

Royal Army Service Corps

The Royal Army Service Corps was a corps of the British Army. It was responsible for land, coastal and lake transport; air despatch; supply of food, water, fuel, and general domestic stores such as clothing, furniture and stationery ; administration of...

 and later the Royal Corps of Transport

Royal Corps of Transport

The Royal Corps of Transport was a British Army Corps formed in 1965 from the transport elements of the Royal Army Service Corps and the movement control element of the Royal Engineers . The depot was Buller Barracks in Aldershot...

, no matter what their trade. When the RCT amalgamated to form the Royal Logistic Corps

Royal Logistic Corps

The Royal Logistic Corps provides logistic support functions to the British Army. It is the largest Corps in the Army, comprising around 17% of its strength...

in 1993 the rank finally disappeared from the British Army.