An anti-tank guided missile (ATGM), anti-tank missile, anti-tank guided weapon (ATGW) or anti-armor guided weapon is a guided missile primarily designed to hit and destroy heavily armored military vehicles. ATGMs range in size from shoulder-launched weapons, which can be transported by a single soldier, to larger tripod-mounted weapons, which require a squad or team to transport and fire, to vehicle and aircraft mounted missile systems. Earlier man-portable anti-tank weapons like anti-tank rifles and magnetic anti-tank mines, generally had very short range, sometimes on the order of metres or tens of metres. Rocket-propelled high-explosive anti-tank (HEAT) systems appeared in World War II and extended range to the order of hundreds of metres, but accuracy was low and hitting targets at these ranges was largely a matter of luck. It was the combination of rocket propulsion and remote wire guidance that made the ATGM much more effective than these earlier weapons, and gave light infantry real capability on the battlefield against post-war tank designs. The introduction of semi-automatic guidance in the 1960s further improved the performance of ATGMs. As of 2016, ATGMs were used by over 130 countries and many non-state actors around the world. Post-Cold-War main battle tanks (MBTs) using composite and reactive armors have proven to be resistant to smaller ATGMs. History World War II Germany developed a design for a wire-guided anti tank missile derived from the Ruhrstahl X-4 air to air missile concept in the closing years of World War II. Known as the X-7, it was probably never used in combat and allegedly had serious guidance to target issues. It never entered service, though a few were produced. Early Cold War: first generation ATGMs First-generation ATGMs use a type of command guidance termed manual command to line of sight (MCLOS). This requires continuous input from an operator using a joystick or similar control system to steer the missile to a target. One disadvantage of this is that an operator must keep the sight's reticle cross hairs on a target and then steer the missile into the cross hairs, i.e., the line-of-sight. To do this, an operator must be well trained (spending many hours on a simulator) and must remain stationary and in view of a target during the flight time of the missile. Because of this, the operator is vulnerable while guiding the missile. The first system to become operational and to see combat was the French