Laser
Light Amplification by Stimulated Emission of Radiation (commonly: "LASER") was discovered on Earth in the early 20th century. Most lasers use a form of crystal or gas in which the electrons have been raised to an excited state. Mirrors are then used to reflect stray photons back and forth through this medium, provoking a cascade reaction that releases a burst of light. The beam emitted from a laser is monochromatic, coherent, and has a very high intensity. High-energy lasers are thus able to focus large amounts of energy onto very small areas, which can result in considerable physical damage.
Lasers have a variety of uses in medicine, computers, mining and power generation (such as fusion reactors) and came into widespread use as a weapon during the mid-21st Century.
Lasers remained in widespread use for some two hundred years, and weas the main armament of the Constitution class starships during the early years of the Federation. By 2255 the standard issue hand laser was capable of blasting through considerable thickness of rock. A larger artillery style ground cannon could provide heavy fire - this weapon could be rigged to run from remote power sources if required, supplying sufficient power to blast half a continent.
Between 2255 and 2265, lasers where replaced in Star Fleet service with the much superior phasers.
Today, lasers are not a significant ship-to-ship weapon, as the navigational shields of a Federation starship are immune to this form of energy.
