Tanks were first used in battle in 1916, before this they had armoured cars but they couldn't go off-road. The first time tanks were used was on 15th September on the western front at The Battle of the Somme, it assisted British soldiers who were attacking German trenches. At first, the main usage of tanks was to break through barbed wire and cross trenches, at first the first tanks were very slow and weak but later designs were very successful and helped end the trench warfare style.
Here is a picture of the first British tank, it had a crew of 3 mean and a maximum speed of 3mph, it wasn't very successful as it couldn't cross trenches and the men could walk faster than it.
This was the Germans first tank; it needed a crew of 18 men! It could travel it 9mph which was much faster than the allies version but it wasn't very good at off-road and often got stuck.
During WW1, planes were armed with machine guns and weren't very accurate or effective, but everybody used them. Towards the end of the war they built bomber planes that could hold two to three bombs each. So, to have any effect they had to build a lot of these types of planes. Planes were mostly used for spying on the enemy and plane vs. plane battles called 'dogfights'.
Aswell as the plane, the Zeppelin (also known as a blimp), was an airship that was used during the early part of the war in bombing attacks by the Germans. They carried machine guns and bombs. However, they were abandoned because they were easy to shoot out of the sky.
The German army were the first to use chlorine gas at the battle of Ypres in...