The major technological advancement that changed warfare in World War I was the introduction of mechanized warfare, including tanks, machine guns, and aircraft. The conflict marked a shift from traditional battle tactics to modern warfare, characterized by trench warfare and mass casualties. Tanks, introduced in significant numbers towards the war's end, were developed to break through stalemated trench lines and provide mobile firepower. Machine guns allowed for devastating defensive capabilities, while aircraft played roles in reconnaissance and bombing. These innovations fundamentally changed military strategies and tactics, shaping future conflicts and leading to higher levels of destruction.