The definition of howitzer differs from time to time.
The first howitzers owe their name to the fact that they fired shells, that is to say hollow projectiles which exploded after their fall, unlike cannons which fired solid balls. They appear in the middle of the 17th century.
The solid cannonball, less effective, disappeared around 1850 and the guns therefore also fired shells. The distinction between cannon and howitzer is then established on the basis of the firing angle:less than 45° it is a cannon, the more it is a howitzer.
From the First World War, artillery pieces that can fire at all elevations appear. Since that time, the determining criterion has been the ratio between the length of the tube and its caliber. Below 20 (25 in the USA) it is a howitzer, above it is a cannon.
In practice the howitzers continue to fire at an inclination greater than 45° (vertical fire); plunging fire (less than 45°) is only intended in the event that a battery is confronted with an attack on its position. As for the guns, as they normally fire at long range, an inclination of less than 45° is preferable. This is because plunging fire makes the projectile's flight time shorter and, therefore, reduces dispersion.
A howitzer is not a mortar because the latter does not have a bolt carrier[1] and is generally loaded through the muzzle, letting the projectile slide down the tube. Currently, it is mainly used by infantry.
The designation howitzer, used among others in the United States, is a word of Czech origin meaning catapult, which dates from the Austro-Hungarian Empire. At that time, Czechs engaged in artillery compared the curved trajectory of the shell with that of the projectile of this weapon.
Modern howitzers are towed or self-propelled (abbreviation SP in English, for Self Propelled; in French, we use the denomination AM, which means AutoMoteur [the French designation is rather "Au" for "self-propelled" (cf 155 Au F1) and "Am" for "self-moving (155 Am F3)], knowing that in France, an artillery piece called "Au" carries on board the ammunition it uses for shooting, while a piece of artillery called "Am" is simply propelled, but does not carry any artillery ammunition SPs are tracked vehicles often equipped with a huge turret making them look like assault tanks.
In the old western camp the most common howitzers were 105 mm caliber for the towed and 105 mm, 155 mm and 8 inches for the SP.
In the former Warsaw Pact the most common calibers were 122 and 152 mm.
Some types of shells
* HE:(High Explosive) explosive either on impact (percussive) or just above the enemy (fusing)
* ILL:(ILLuminating) illuminating (the shell releases an illuminating pot hanging from a parachute)
* HEAT:(High Explosive Anti Tank) for direct fire against armored vehicles (if the artillery position is overrun). The American M107 shell weighs 19.6 kg (including 15.8% explosive) and is 800 mm long
* SMK:(SMoKe, smoke) smoke generator
* gas:endowment in the former Warsaw Pact
* Naked:8 inch Howitzers have nuclear capability