Answer:
Well I don't know what "No Man's Land" is but I can help you. World War I featured new technology, but accompanied with the devastating military strategy called "trench warfare". New technologies included the machine gun, airplanes, and chemical warfare (poisonous gases). But the military strategy used was trench warfare, which consisted of soldiers staying in wide trenches, and brash charges toward the opposing trench (where the enemy was). It gained little land and dealt heavy casualties, especially because the new technologies were much better at killing large amounts of people. The need for a new military strategy comes from these enormous amounts of casualties, generals couldn't just throw their soldiers at the enemy any more, more tactical operations were needed.