When were tanks first used?

Tanks were first used in combat during World War I by the British Army on September 15, 1916, at the Battle of the Somme. This was the first time in history that armored vehicles were used in a military conflict, and while the initial use of tanks was not particularly effective, their potential was quickly recognized. They were developed further, and became a vital part of warfare during World War II, and remain so to this day.