A major advancement in warfare introduced during World War I was the widespread use of machine guns. These weapons transformed battlefield tactics by allowing a small number of troops to defend positions effectively against larger forces. Machine guns caused significant casualties and altered the dynamics of trench warfare, leading to a stalemate on the Western Front. Their rapid-fire capability made traditional infantry charges deadly, forcing armies to develop new strategies, such as trench systems and artillery support. This shift highlighted the brutal nature of modern warfare and underscored technological advancements' role in military conflict during the early 20th century.