GrenadeA grenade is an explosive weapon typically thrown by hand (also called hand grenade), but can also refer to a shell (explosive projectile) shot from the muzzle of a rifle (as a rifle grenade) or a grenade launcher. A modern hand grenade generally consists of an explosive charge ("filler"), a detonator mechanism, an internal striker to trigger the detonator, an arming safety secured by a transport safety.
MinenwerferMinenwerfer ("mine launcher" or "mine thrower") is the German name for a class of short range mine shell launching mortars used extensively during the First World War by the Imperial German Army. The weapons were intended to be used by engineers to clear obstacles including bunkers and barbed wire, that longer range artillery would not be able to target accurately. The Germans studied the Siege of Port Arthur, where heavy artillery had been unable to destroy defensive structures like barbed wire and bunkers.
Mortar (weapon)A mortar is usually a simple, lightweight, man-portable, muzzle-loaded weapon, consisting of a smooth-bore (although some models use a rifled barrel) metal tube fixed to a base plate (to spread out the recoil) with a lightweight bipod mount and a sight. They launch explosive shells (technically called bombs) in high-arcing ballistic trajectories. Mortars are typically used as indirect fire weapons for close fire support with a variety of ammunition. Mortars have been used for hundreds of years.
Trench warfareTrench warfare is the type of land warfare using occupied lines largely comprising military trenches, in which troops are well-protected from the enemy's small arms fire and are substantially sheltered from artillery. It became archetypically associated with World War I (1914–1918), when the Race to the Sea rapidly expanded trench use on the Western Front starting in September 1914. Trench warfare proliferated when a revolution in firepower was not matched by similar advances in mobility, resulting in a grueling form of warfare in which the defender held the advantage.