Shrapnel shell in the context of "Artillery bombardment"

A shell, in a modern military context, is a projectile whose payload contains an explosive, incendiary, or other chemical filling. Originally it was called a bombshell, but "shell" has come to be unambiguous in a military context. A shell can hold a tracer.

All explosive- and incendiary-filled projectiles, particularly for mortars, were originally called grenades, derived from the French word for pomegranate, so called because of the similarity of shape and that the multi-seeded fruit resembles the powder-filled, fragmentizing bomb. Words cognate with grenade are still used for an artillery or mortar projectile in some European languages.

In military usage, a barrage is massed sustained artillery fire (shelling) aimed at a series of points along a line. In addition to attacking any enemy in the kill zone, a barrage intends to suppress enemy movements and deny access across that line of barrage. The impact points along the line may be 20 to 30 yards apart, with the total line length of the barrage zone anything from a few hundred to several thousand yards long. Barrages can consist of multiple such lines, usually about 100 yards apart, with the barrage shifting from one line to the next over time, or several lines may be targeted simultaneously.

A barrage may involve a few or many artillery batteries, or even (rarely) a single gun. Typically each gun in a barrage, using indirect fire, will fire continuously at a steady rate at its assigned point for an assigned time before moving onto the next target, following the barrage's detailed timetable. Barrages typically use high-explosive shells, but may also be shrapnel, smoke, illumination, poison gas (in World War I), or potentially other chemical agents. Barrages are in contrast with concentrated artillery fire, which has a single specific target such as a known enemy position or structure, and in contrast with direct fire which targets enemies within the direct line of sight of the gun.

The German S-mine (Schrapnellmine, Springmine or Splittermine in German), known by enemy Allied Forces as the "Bouncing Betty" on the Western Front and "frog-mine" on the Eastern Front, is the best-known version of a class of mines known as bounding mines. When triggered, these mines are launched into the air and then detonated at about one metre (3 ft) from the ground. The explosion projects a lethal spray of shrapnel in all directions. The S-mine was an anti-personnel mine developed by Germany in the 1930s and used extensively by German forces during World War II. It was designed to be used in open areas against unshielded infantry. Two versions were produced, designated by the year of their first production: the SMi-35 and SMi-44. There are only minor differences between the two models.

The S-mine entered production in 1935 and served as a key part of the defensive strategy of the Wehrmacht. Until production ceased in 1945, Germany produced over 1.93 million S-mines. These mines inflicted heavy casualties and slowed, or even repelled, drives into German-held territory throughout the war. The design was lethal, successful, and often imitated.

A barrel bomb is an improvised unguided bomb, sometimes described as a flying IED (improvised explosive device). They are typically made from a large barrel-shaped metal container that has been filled with explosives, possibly shrapnel, oil or chemicals as well, and then dropped from a helicopter or aeroplane. Due to the large amount of explosives (up to 1,000 kilograms (2,200 lb)), their poor accuracy, and indiscriminate use in populated civilian areas (including refugee camps), the resulting impacts have been devastating. Critics have characterised them as weapons of terror and illegal under international conventions.

Barrel bombs were used in different conflict zones including in 1948 and by the US military in Vietnam in the late 1960s. Starting in the 1990s, they were also used in Sri Lanka, Croatia and Sudan. Barrel bombs were used extensively by the Syrian Air Force during the Syrian civil war—bringing the weapon to widespread global attention—and later by the Iraqi forces during the Anbar campaign. Experts believe they will continue to be embraced by unstable nations fighting insurgencies since they are cheap to make and utilise the advantages of a government's airpower.