How did World War I change the way wars were fought?

World War I marked a significant shift in warfare due to the introduction of advanced technologies such as machine guns, tanks, and chemical weapons, which changed battlefield dynamics. The war also saw the extensive use of trench warfare, leading to prolonged stalemates and a focus on attrition rather than decisive victories. Additionally, the need for total mobilization of nations brought about new strategies in logistics and coordination, influencing future military conflicts. Overall, WWI set the stage for modern warfare, emphasizing industrial capabilities and the importance of air power and mechanized units.