Combat knives are designed for military use, more specifically for close combat.  Since trench warfare is no longer used, most combat knives are designed for utility/tool use such as, clearing foliage, chopping branches for cover, opening ammunition crates, as well as other daily tasks our men in the military are faces with.   With all the different things these knives can do, they are still good for hand-to-hand combat.

Daggers and dirks have been associated with combat knives for centuries.  The English are credited with being the first to combine utility with defense when they began using the kidney dagger in 1350.  In response, French and Italian daggers were introduced in the 14th century.  These knives had tapered and double edge points to help their fighters penetrate the new armor designs. 

As firearms became more popular, the use of combat knives was on the decline until 1827 when James Bowie introduced the Bowie Knife.  These knives were and still are strong knives with a sold design.  These knives proved to be a good replacement for different tools such as the tomahawk and sometimes even a sidearm.  These knives also proved to be a great companion for hunters. Some of the larger knives were big enough to be used a machetes. 

Today, combat knives coming in many shapes and sizes with most soldiers carrying their governments standard issue combat knife.  The Chilean Commando forces are trained to use the Corvo knife, a knife they have been using for generations.  The Gurkha regiments use the Kukri, a broad-bladed curved weapon that closely resembles a machete more than a knife.  In the United States Marine Corps, the standard issue combat knife is the KA-BAR knife.  They have been using this knife since World War II.