There is not any specific prohibition against the use of fully automatic weapons ("machine guns") in warfare in the Geneva Convention treaties or any others with which I am familiar.
Countries which have laws against automatic weapons generally write them in such a way that they specifically do not apply to properly authorized agents of government (such as soldiers) using them in the course of their duties.
Yes, they did have machine guns in WW2
Yes. There were machine guns in WW1. There were Gatlin Guns, a type of machine gun, in the Civil War.Yes
the machine guns
Machine guns were in use BEFORE WW 1. They were around for the entire war.
Not actual machine guns, but something of a predecessor to it - the hand cranked Gatling Gun.
The Bren light machine guns were used in World War II, the Korean war, the Falklands War and the 1991 Gulf War. Bren light guns were a series of light machine guns adopted by the British in the 1930's.
All of the major players in WWI possessed machine guns before the outbreak of the war.
All of the major players possessed machine guns by the outbreak of the war.
No
Most of the parties involved already had machine guns in their inventory prior to the outbreak of the First World War.
Machine guns have a higer rate of fire and so they shoot bulets faster
In World War 2 there were three types of machine guns used: squad support weapon, medium machine gun, and Heavy Machine gun such as the Browning M2, and the M1919