World War I brought about a major change in how wars were fought by introducing both mechanization and technology to the battlefield. Aviation, submarines, chemical warfare, armored vehicles, tanks, machine guns and wireless communication significantly altered the dynamics of the war from those preceding it. Many of the war's technological advancements were a result of the need to overcome the trench warfare conditions that stalemated the conflict and transformed it into a costly war of attrition.
The machine gun was a recently-developed weapon that had a significant effect on how World War I was fought. Its capability of shooting hundreds of bullets a minute at targets that were up to 4,000 yards away provided an advantage to the defenders' trenches. The attackers were quickly mowed down before they could reach the defenders' entrenched positions. In this way, the machine gun not only contributed to the mass slaughter that was characteristic of World War I trench warfare, it also created the need for the armored vehicles that could safely cross the area between the opposing trenches known as "no-man's-land." This became the primary cause for the development of new technologies that could provide protected mobility and long-range assault capabilities.
The first chemical weapons and aerial bombardments were an additional response to the stalemate. Indirect artillery fire was also employed when enemy positions were not visible. Reconnaissance by aerial balloons and listening devices began to be used to help direct artillery shells to their targets. Flame throwers first came into use during World War I. Handheld submachine guns and light automatic weapons were also developed and used for the first time during this war.