Airplanes: World War I saw the rapid development of aviation technology. Airplanes were used for reconnaissance, bombing, and dogfighting. The war also saw the development of the first aircraft carriers.
Machine guns: Machine guns were one of the most devastating weapons of World War I. They could fire hundreds of rounds per minute and could mow down entire platoons of soldiers.
Artillery: Artillery was used extensively in World War I to bombard enemy positions. Long-range artillery pieces could fire shells from miles away, destroying entire towns and villages.
Submarines: Submarines were used by both sides in World War I. They were used to attack enemy shipping and to lay mines. German U-boats were particularly effective in sinking Allied ships.
Poison gas: Poison gas was first used by the Germans in 1915. It was a horrific weapon that could cause blindness, suffocation, and death. Both sides used poison gas in the war, resulting in hundreds of thousands of casualties.
Flamethrowers: Flamethrowers were used to clear enemy trenches and bunkers. They were devastating weapons that could inflict terrible burns and cause psychological terror.
Barbed wire: Barbed wire was used extensively in World War I to create obstacles and fortify defensive positions. It was a major deterrent to infantry attacks and could cause severe injuries.
Trench warfare: World War I is often remembered for its bloody trench warfare. Trenches were deep ditches that protected soldiers from enemy fire. They were often squalid and disease-ridden, and many soldiers died from disease or malnutrition.