What were the 4 new types of technology in war world 1?

1. Tanks

2. Machine guns

3. Poison gas

4. Trench warfare

Actually, only the first of the above list were "new" technologies. All of the others were invented long beforehand, and were used in other conflicts well before WW1.

A list of technologies first effectively employed in WW1; that is, while the underlying technology was, in most cases, developed before the war, WW1 is the first time a practical version of the technology was widely used.

1. tanks
2. airplanes
3. indirect-fire artillery with correction by a forward observer
4. submarines
5. telephone and wireless communications

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