Distinguishing features of the War
The First World War was different from prior military conflicts: it was a meeting of 20th century technology with 19th century mentality and tactics. This time, millions of soldiers fought on all sides and the casualties were enormous, mostly because of the more efficient weapons (like artillery and machine guns) that were used in large quantities against old tactics. Although the First World War led to the development of air forces, tanks, and new tactics (like the Rolling barrage and Crossfire), much of the action took place in the trenches, where thousands died for each square metre of land gained. The First World War also saw the use of chemical warfare, and aerial bombardment, both of which had been outlawed under the 1909 Hague Convention. The effects of gas warfare were to prove long-lasting, both on the bodies of its victims (many of whom, having survived the war, continued to suffer in later life) and on the minds of a later generation of war leaders (Second World War) who, having seen the effects of gas warfare in the Great War, were reluctant to use it for fear that the enemy would retaliate and might have better weaponry.
Weaponry
Notable infantry weaponry of World War 1 included the Maxim machine gun and the cannons without recoil as the French 75. British forces used the Lewis gun and Webley. American forces used the Browning Automatic Rifle and M1911. German forces used the Karabiner 98k and Luger. French forces used the Chauchat.
A deadly war
Many of the deadliest battles in history occurred in this war. See Ypres, Vimy Ridge, Marne, Cambrai, Somme, Verdun, Gallipoli. See Wars of the 20th Century for various totals given for the number that died in this war. For instance, is it proper to consider the Influenza pandemic (see below) as part of the overall death count for the war, given the important part the War played in its transmission?
Aftermath
Due to the length of this article, see the Aftermath of World War I for events and repercussions following the armistice, which includes: