Coastal artillery in the context of "Corregidor Island"

A field gun is a field artillery piece. Originally the term referred to smaller guns that could accompany a field army on the march, that when in combat could be moved about the battlefield in response to changing circumstances (field artillery), as opposed to guns installed in a fort (garrison artillery or coastal artillery), or to siege cannons and mortars which are too large to be moved quickly, and would be used only in a prolonged siege.

Perhaps the most famous use of the field gun in terms of advanced tactics was Napoleon Bonaparte's use of very large wheels on the guns that allowed them to be moved quickly even during a battle. By moving the guns from point to point during a battle, enemy formations could be broken up to be handled by the infantry or cavalry wherever they were massing, dramatically increasing the overall effectiveness of the attack.

Coastal defence (or defense) and coastal fortification are measures taken to provide protection against military attack at or near a coastline (or other shoreline), for example, fortifications and coastal artillery. Because an invading enemy normally requires a port or harbour to sustain operations, such defences are usually concentrated around such facilities, or places where such facilities could be constructed. Coastal artillery fortifications generally followed the development of land fortifications, usually incorporating land defences; sometimes separate land defence forts were built to protect coastal forts. Through the middle 19th century, coastal forts could be bastion forts, star forts, polygonal forts, or sea forts, the first three types often with detached gun batteries called "water batteries". Coastal defence weapons throughout history were heavy naval guns or weapons based on them, often supplemented by lighter weapons. In the late 19th century separate batteries of coastal artillery replaced forts in some countries; in some areas these became widely separated geographically through the mid-20th century as weapon ranges increased. The amount of landward defence provided began to vary by country from the late 19th century; by 1900 new US forts almost totally neglected these defences. Booms were also usually part of a protected harbor's defences. In the middle 19th century underwater minefields and later controlled mines were often used, or stored in peacetime to be available in wartime. With the rise of the submarine threat at the beginning of the 20th century, anti-submarine nets were used extensively, usually added to boom defences, with major warships often being equipped with them (to allow rapid deployment once the ship was anchored or moored) through early World War I. In World War I railway artillery emerged and soon became part of coastal artillery in some countries; with railway artillery in coast defence some type of revolving mount had to be provided to allow tracking of fast-moving targets.

In littoral warfare, coastal defence counteracts naval offence, such as naval artillery, naval infantry (marines), or both.

A bunker is a defensive fortification designed to protect people and valued materials from falling bombs, artillery, or other attacks. Bunkers are almost always underground, in contrast to blockhouses which are mostly above ground. They were used extensively in World War I, World War II, and the Cold War for weapons facilities, command and control centers, storage facilities, etc. Bunkers can also be used as protection from tornadoes.

Trench bunkers are small concrete structures, partly dug into the ground. Many artillery installations, especially for coastal artillery, have historically been protected by extensive bunker systems. Typical industrial bunkers include mining sites, food storage areas, dumps for materials, data storage, and sometimes living quarters. When a house is purpose-built with a bunker, the normal location is a reinforced below-ground bathroom with fiber-reinforced plastic shells. Bunkers deflect the blast wave from nearby explosions to prevent ear and internal injuries to people sheltering in the bunker. Nuclear bunkers must also cope with the underpressure that lasts for several seconds after the shock wave passes, and block radiation.

The Royal Garrison Artillery (RGA) was formed in 1899 as a distinct arm of the British Army's Royal Regiment of Artillery serving alongside the other two arms of the Regiment, the Royal Field Artillery (RFA) and the Royal Horse Artillery (RHA). The RGA were the 'technical' branch of the Royal Artillery who were responsible for much of the professionalisation of technical gunnery that was to occur during the First World War. It was originally established to man the guns of the British Empire's forts and fortresses, including coastal artillery batteries, the heavy gun batteries attached to each infantry division and the guns of the siege artillery. The RGA was amalgamated with the RFA in 1924, from which time the only two arms within the Royal Regiment of Artillery have been the Royal Artillery and the Royal Horse Artillery.

The Dover Strait coastal guns were long-range coastal artillery batteries that were sited on both sides of the English Channel during the Second World War. The British built several gun positions along the coast of Kent, England while the Germans fortified the Pas-de-Calais in occupied France. The Strait of Dover was strategically important because it is the narrowest part of the English channel. Batteries on both sides attacked shipping as well as bombarding the coastal towns and military installations. The German fortifications would be incorporated into the Atlantic Wall which was built between 1942 and 1944.