Directed Energy Weapons (DEW) have been a recurring theme in science fiction literature and cinema ever since H.G. Wells published the 'War of the Worlds' in 1898. The idea of a 'death ray' which can instantly destroy or burn a target at a distance retains its allure to this very day. More than a century after Wells contrived his 'heat ray', the technology is maturing to the point of becoming soon deployable.

High Energy Laser weapons have been progressively evolving since the 1960s, a path punctuated by a series of important scientific breakthroughs and engineering milestones.

The popular view of a HEL, seen as constructing a great big laser and pointing it at a target with the intention of vapourising it, bears only vague similarity to a real HEL weapon. There are genuine technological and operational challenges involved in creating truly useful and effective weapons.

Kinetic or projectile weapons such as guns, missiles and bombs destroy targets by kinetic effects, including overpressure, projectile, shrapnel and spalling damage, and incendiary effects. The result is structural damage and fire, which can and often will cause fatal damage to a target. A kinetic weapon thus uses stored chemical energy in propellants and warhead explosives, the latter where used, and delivers this energy to a target by means of a projectile of some kind. Whether the projectile weapon is a trebuchet tossing a large rock over 300 yards, or a multimode seeker equipped long range air to air missile hitting an aircraft from 200 nautical miles away, the underpinning principle is much the same, only the implementation is different.