Fire-control system
Rangefinder telescopes on a separate mounting measured the distance to the target. These measurements were converted by the Fire Control Table into the bearings and elevations for the guns to fire upon. In the turrets, the gunlayers adjusted the elevation of their guns to match an indicator for the elevation transmitted from the Fire Control table—a turret layer did the same for bearing. When the guns were on target they were centrally fired.
Even with as much mechanization of the process, it still required a large human element; the Transmitting Station (the room that housed the Dreyer table) for HMS Hood's main guns housed 27 crew.
Directors were largely unprotected from enemy fire. It was difficult to put much weight of armour so high up on the ship, and even if the armour did stop a shot, the impact alone would likely knock the instruments out of alignment. Sufficient armour to protect from smaller shells and fragments from hits to other parts of the ship was the limit.

The performance of the analog computer was impressive. The battleship USS North Carolina during a 1945 test was able to maintain an accurate firing solution on a target during a series of high-speed turns.
 It is a major advantage for a warship to be able to maneuver while engaging a target.
Night naval engagements at long range became feasible when radar data could be input to the rangekeeper. The effectiveness of this combination was demonstrated in November 1942 at the Third Battle of Savo Island when the USS Washington engaged the Japanese battleship Kirishima at a range of 8,400 yards (7.7 km) at night.  Kirishima was set aflame, suffered a number of explosions, and was scuttled by her crew. She had been hit by at least nine 16-inch (410 mm) rounds out of 75 fired (12% hit rate).
The wreck of Kirishima was discovered in 1992 and showed that the entire bow section of the ship was missing.
The Japanese during World War II did not develop radar or automated fire control to the level of the US Navy and were at a significant disadvantage.

Post-1945: By the 1950s gun turrets were increasingly unmanned, with gun laying controlled remotely from the ship's control centre using inputs from radar and other sources.
The last combat action for the analog rangekeepers, at least for the US Navy, was in the 1991 Persian Gulf War when the rangekeepers on the Iowa-class battleships directed their last rounds in combat.

Aircraft based fire control: 

World War II bomb sights: An early use of fire-control systems was in bomber aircraft, with the use of computing bombsights that accepted altitude and airspeed information to predict and display the impact point of a bomb released at that time. The best known United States device was the Norden bombsight.

World War II aerial gunnery sights: Simple systems, known as lead computing sights also made their appearance inside aircraft late in the war as gyro gunsights. These devices used a gyroscope to measure turn rates, and moved the gunsight's aim-point to take this into account, with the aim point presented through a reflector sight. The only manual "input" to the sight was the target distance, which was typically handled by dialing in the size of the target's wing span at some known range. Small radar units were added in the post-war period to automate even this input, but it was some time before they were fast enough to make the pilots completely happy with them. The first implementation of a centralized fire control system in a production aircraft was on the B-29.

Post-World War II systems: By the start of the Vietnam War, a new computerized bombing predictor, called the Low Altitude Bombing System (LABS), began to be integrated into the systems of aircraft equipped to carry nuclear armaments. This new bomb computer was revolutionary in that the release command for the bomb was given by the computer, not the pilot; the pilot designated the target using the radar or other targeting system, then "consented" to release the weapon, and the computer then did so at a calculated "release point" some seconds later. This is very different from previous systems, which, though they had also become computerized, still calculated an "impact point" showing where the bomb would fall if the bomb were released at that moment. The key advantage is that the weapon can be released accurately even when the plane is maneuvering. Most bombsights until this time required that the plane maintain a constant attitude (usually level), though dive-bombing sights were also common.
The LABS system was originally designed to facilitate a tactic called toss bombing, to allow the aircraft to remain out of range of a weapon's blast radius. The principle of calculating the release point, however, was eventually integrated into the fire control computers of later bombers and strike aircraft, allowing level, dive and toss bombing. In addition, as the fire control computer became integrated with ordnance systems, the computer can take the flight characteristics of the weapon to be launched into account.

Land based fire control: 

Anti-aircraft based fire control: By the start of World War II, aircraft altitude performance had increased so much that anti-aircraft guns had similar predictive problems, and were increasingly equipped with fire-control computers. The main difference between these systems and the ones on ships was size and speed. The early versions of the High Angle Control System, or HACS, of Britain's Royal Navy were examples of a system that predicted based upon the assumption that target speed, direction, and altitude would remain constant during the prediction cycle, which consisted of the time to fuze the shell and the time of flight of the shell to the target. The USN Mk 37 system made similar assumptions except that it could predict assuming a constant rate of altitude change. The Kerrison Predictor is an example of a system that was built to solve laying in "real time", simply by pointing the director at the target and then aiming the gun at a pointer it directed. It was also deliberately designed to be small and light, in order to allow it to be easily moved along with the guns it served.
The radar-based M-9/SCR-584 Anti-Aircraft System was used to direct air defense artillery since 1943.  The MIT Radiation Lab's SCR-584 was the first radar system with automatic following, Bell Laboratory's M-9 was an electronic analog fire-control computer that replaced complicated and difficult-to-manufacture mechanical computers (such as the Sperry M-7 or British Kerrison predictor). In combination with the VT proximity fuze, this system accomplished the astonishing feat of shooting down V-1 cruise missiles with less than 100 shells per plane (thousands were typical in earlier AA systems). This system was instrumental in the defense of London and Antwerp against the V-1.
Although listed in Land based fire control section anti-aircraft fire control systems can also be found on naval and aircraft systems.

Coast artillery fire control: In the United States Army Coast Artillery Corps, Coast Artillery fire control systems began to be developed at the end of the 19th century and progressed on through World War II.
Early systems made use of multiple observation or base end stations (see Figure 1) to find and track targets attacking American harbors. Data from these stations were then passed to plotting rooms, where analog mechanical devices, such as the plotting board, were used to estimate targets' positions and derive firing data for batteries of coastal guns assigned to interdict them.
U.S. Coast Artillery forts bristled with a variety of armament, ranging from 12-inch coast defense mortars, through 3-inch and 6-inch mid-range artillery, to the larger guns, which included 10-inch and 12-inch barbette and disappearing carriage guns, 14-inch railroad artillery, and 16-inch cannon installed just prior to and up through World War II.
Fire control in the Coast Artillery became more and more sophisticated in terms of correcting firing data for such factors as weather conditions, the condition of powder used, or the Earth's rotation. Provisions were also made for adjusting firing data for the observed fall of shells. As shown in Figure 2, all of these data were fed back to the plotting rooms on a finely tuned schedule controlled by a system of time interval bells that rang throughout each harbor defense system.
It was only later in World War II that electro-mechanical gun data computers, connected to coast defense radars, began to replace optical observation and manual plotting methods in controlling coast artillery. Even then, the manual methods were retained as a back-up through the end of the war.

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.