The multiple integrated laser engagement system, or MILES, is used by the U.S. military and other armed forces around the world for training purposes. It uses lasers and blank cartridges to simulate actual battle. Individual soldiers carry small laser sensors scattered over their bodies, which detect when the soldier has been illuminated by a firearm's laser. Each laser transmitter is set to mimic the effective range of the weapon on which it is used. When a person is "hit", a medic can use the digital readout to determine which first aid method to practice. Different versions of MILES systems are available to both US and international militaries. The capabilities of the individual systems can vary significantly but in general all modern systems carry information about the shooter, weapon and ammunition in the laser. When this information is received by the target, the target's MILES system uses a random number roll and a casualty probability lookup table to determine the outcome. For example, a MILES transmitter emulating an M16 rifle cannot harm an armored personnel carrier (APC), but could still "kill" a commander visible in the hatch of the vehicle. Vehicles are typically outfitted with a belt of laser sensors or individual wireless detectors. Dismounted soldiers often wear a vest or harness with sensors as well as a "halo" of sensors on their helmets. MILES systems can be coupled with a real-time data link allowing position and event data to be transmitted back to a central site for data collection and display. More sophisticated systems for tanks and APCs exist that use various techniques (including scanning lasers and coupled radio systems) to allow more precise targeting of armored vehicles. The standard is maintained by the U.S. Army's PEO-STRI branch. Early versions MILES was introduced to the U.S. Army for direct-fire, force-on-force training capability at home stations and combat training centers during operational testing in 1978 and 1979 following the conclusion of the US Army's Engineering Development program awarded to Xerox Electro-Optical Systems. The goal of the program was to design and build a tactical training system that simulates the weapons, weapon characteristics and effects of a family of weapon systems including infantry, armor and aircraft, with an initial design of 11 systems including rifles, tank guns, and missiles. MILES systems used a laser module which was mounted to the barrel of a real weapon, a blank-firing adaptor for the weapon, and