A trench knife was first used during World War I. Its sole purpose was to kill an opponent in close quarter combats. The original design of the trench knife was actually customized for this very purpose. It was quite useful during that time, thus the trench knife is still used today. Suppliers of military equipment as well as other knives offer trench knife to knife enthusiasts. But because of modern times, the designs have changed as well. Yet others still retain the quality it had in the First as well as the Second World Wars.
The main feature of the trench knife is that it is very short and it allows the soldier to use this in confined combats. It is also very sharp. The blade is often times straight but can groove to a certain angle as preferred by the user. The earliest design of the trench knife was used as a personal weapon. In fact, it can be made from bayonets or swords, just by shortening these weapons. That time, it was highly advisable to do this.
Soldiers use trench knife when they go over walls and through the trenches of their opponents. The blade can be safely used in cramped as well as crowded trenches. This is why it earned the nickname of being a silent weapon. Scouts and other people who go through the wall remove the sentries by using the trench knife that they hide within their clothing. This is simply because this knife does not attract any attention.