Automatic weapons are those which reload without any action from the shooter. The sequence of events, which begin with pulling the trigger, allow the gun to continuously reload. The gun also continues to fire when the shooter pulls the trigger just one time and holds the trigger until they want the gun to stop firing. Semi-automatic weapons are very similar to automatic weapons, except that they only fire one bullet with each trigger pull.
Automatic weapons are often used in wars. Soldiers can focus on aiming the automatic weapons, rather than reloading. Once the trigger is pulled, they simply move the gun as the target moves. However, automatic weapons can jam and if the shooter becomes injured and they release the trigger, the gun will stop firing. Technology on automatic weapons has become much more stable, lessening the chance that the gun will jam.
Semi-automatic weapons are also used in wars. The gun can also be prone to jamming. However, they are highly effective because the shooter simply needs to pull the trigger for each shot and does not have to be concerned with loading the weapon, as it does it automatically, in the same way that an automatic weapon does. The action of firing the weapon, allows the weapon to pull in more ammunition. The only difference between an automatic weapon and a semi automatic weapon in the need to continuously pull the trigger on a semi automatic weapon.