Fire-control system
Direct and indirect fire control systems: Land based fire control systems can be used to aid in both Direct fire and Indirect fire weapon engagement. These systems can be found on weapons ranging from small handguns to large artillery weapons.

Modern fire control systems: Modern fire-control computers, like all high-performance computers, are digital. The added performance allows basically any input to be added, from air density and wind, to wear on the barrels and distortion due to heating. These sorts of effects are noticeable for any sort of gun, and fire-control computers have started appearing on smaller and smaller platforms. Tanks were one early use that automated gun laying had, using a laser rangefinder and a barrel-distortion meter. Fire-control computers are useful not just for aiming large cannons, but also for aiming machine guns, small cannons, guided missiles, rifles, grenades, and rockets—any kind of weapon that can have its launch or firing parameters varied. They are typically installed on ships, submarines, aircraft, tanks and even on some small arms—for example, the grenade launcher developed for use on the Fabrique Nationale F2000 bullpup assault rifle. Fire-control computers have gone through all the stages of technology that computers have, with some designs based upon analogue technology and later vacuum tubes which were later replaced with transistors.
Fire-control systems are often interfaced with sensors (such as sonar, radar, infra-red search and track, laser range-finders, anemometers, wind vanes, thermometers, barometers, etc.) in order to cut down or eliminate the amount of information that must be manually entered in order to calculate an effective solution. Sonar, radar, IRST and range-finders can give the system the direction to and/or distance of the target. Alternatively, an optical sight can be provided that an operator can simply point at the target, which is easier than having someone input the range using other methods and gives the target less warning that it is being tracked. Typically, weapons fired over long ranges need environmental information—the farther a munition travels, the more the wind, temperature, air density, etc. will affect its trajectory, so having accurate information is essential for a good solution. Sometimes, for very long-range rockets, environmental data has to be obtained at high altitudes or in between the launching point and the target. Often, satellites or balloons are used to gather this information.
Once the firing solution is calculated, many modern fire-control systems are also able to aim and fire the weapon(s). Once again, this is in the interest of speed and accuracy, and in the case of a vehicle like an aircraft or tank, in order to allow the pilot/gunner/etc. to perform other actions simultaneously, such as tracking the target or flying the aircraft. Even if the system is unable to aim the weapon itself, for example the fixed cannon on an aircraft, it is able to give the operator cues on how to aim. Typically, the cannon points straight ahead and the pilot must maneuver the aircraft so that it oriented correctly before firing. In most aircraft the aiming cue takes the form of a "pipper" which is projected on the heads-up display (HUD). The pipper shows the pilot where the target must be relative to the aircraft in order to hit it. Once the pilot maneuvers the aircraft so that the target and pipper are superimposed, he or she fires the weapon, or on some aircraft the weapon will fire automatically at this point, in order to overcome the delay of the pilot. In the case of a missile launch, the fire-control computer may give the pilot feedback about whether the target is in range of the missile and how likely the missile is to hit if launched at any particular moment. The pilot will then wait until the probability reading is satisfactorily high before launching the weapon.

See also: Target acquisition
Counter-battery radar
Director (military)
Fire-control radar
List of U.S. Army fire control and sighting material by supply catalog designation
Predicted impact point
Ship gun fire-control systems
Tartar Guided Missile Fire Control System

References: 

Further reading: Baxter, James Phinney (1946). Scientists Against Time. Little, Brown and Company. ISBN 0-26252-012-5.
Campbell, John (1985). Naval Weapons of World War Two. Naval Institute Press. ISBN 0-87021-459-4.
Fairfield, A.P. (1921). Naval Ordnance. The Lord Baltimore Press.
Frieden, David R. (1985). Principles of Naval Weapons Systems. Naval Institute Press. ISBN 0-87021-537-X.
Friedman, Norman (2008). Naval Firepower: Battleship Guns and Gunnery in the Dreadnought Era. Seaforth. ISBN 978-1-84415-701-3.
Hans, Mort; Taranovich, Steve (10 December 2012). "Design hindsight from the tail-gunner position of a WWII bomber, Part one". EDN. Retrieved 18 August 2020.
Pollen, Antony (1980). The Great Gunnery Scandal — The Mystery of Jutland. Collins. ISBN 0-00-216298-9.
Roch, Axel. "Fire-Control and Human-Computer Interaction: Towards a History of the Computer Mouse (1940-1965)". Stanford University. Archived from the original on 15 February 2020. Retrieved 18 August 2020.
Schleihauf, William (2001). "The Dumaresq and the Dreyer". Warship International. XXXVIII (1). International Naval Research Organization: 6–29. ISSN 0043-0374.
Schleihauf, William (2001). "The Dumaresq and the Dreyer, Part II". Warship International. XXXVIII (2). International Naval Research Organization: 164–201. ISSN 0043-0374.
Schleihauf, William (2001). "The Dumaresq and the Dreyer, Part III". Warship International. XXXVIII (3). International Naval Research Organization: 221–233. ISSN 0043-0374.
Wright, Christopher C. (2004). "Questions on the Effectiveness of U.S. Navy Battleship Gunnery: Notes on the Origin of U.S. Navy Gun Fire Control System Range Keepers". Warship International. XLI (1): 55–78. ISSN 0043-0374.

External links: 
Between Human and Machine: Feedback, Control, and Computing Before Cybernetics – Google Books
BASIC programs for battleship and antiaircraft gun fire control Archived 2012-10-03 at the Wayback Machine
National Fire Control Symposium