Machine pistol in the context of Handgun

A pistol is a type of handgun, characterized by a barrel with an integral chamber. The word "pistol" derives from the Middle French pistolet (c. 1550), meaning a small gun or knife, and first appeared in the English language c. 1570 when early handguns were produced in Europe. In colloquial usage, the word "pistol" is often used as a generic term to describe any type of handgun, inclusive of revolvers (which have a single barrel and a separate cylinder housing multiple chambers) and the pocket-sized derringers (which are often multi-barrelled).

The most common type of pistol used in the contemporary era is the semi-automatic pistol. The older single-shot and lever-action pistols are now rarely seen and used primarily for nostalgic hunting and historical reenactment. Fully-automatic machine pistols are uncommon in civilian usage because of their generally poor recoil-controllability (due to the lack of a buttstock) and strict laws and regulations governing their manufacture and sale (where they are regarded as submachine gun equivalents).

A derringer or deringer is a small handgun that is neither a revolver, semi-automatic pistol, nor machine pistol. It is not to be confused with mini-revolvers or pocket pistols, although some later derringers were manufactured with the pepperbox configuration. The modern derringer is often multi barreled, and is generally the smallest usable handgun of any given caliber and barrel length due to the lack of a moving action, which takes up more space behind the barrel. It is frequently associated with discreet use by women because it is easily concealable in a purse or a stocking.

The original Philadelphia Deringer was a muzzleloading caplock single-shot pistol introduced in 1825 by Henry Deringer. In total, approximately 15,000 Deringer pistols were manufactured. All were single-barrel pistols with back-action percussion locks, typically .41 caliber with rifled bores and walnut stocks. Barrel length varied from 1.5 to 6 in (38 to 152 mm), and the hardware was commonly a copper-nickel alloy known as "German silver".

A semi-automatic pistol (also called a self-loading pistol, autopistol, or autoloading pistol) is a repeating handgun that automatically ejects and loads cartridges in its chamber after every shot fired, but only one round of ammunition is fired each time the trigger is pulled. The pistol's fire control group disconnects the trigger mechanism from the firing pin/striker until the trigger has been released and reset manually, unlike the self-cycled firing mechanism in fully automatic pistols.

A semi-automatic pistol recycles part of the energy released by the propellant combustion to move its bolt, which is usually housed inside the slide. After a round of ammunition is fired, the spent cartridge casing is extracted and ejected as the slide/bolt moves rearwards under recoil, the hammer/striker is cocked by the slide/bolt movement, and a new round from the magazine is pushed into the chamber when the slide/bolt returns forward under spring tension. This sets up the following shot (i.e. "in battery"), which is fired as soon as the trigger is pulled again. Most pistols use a short recoil operation to perform this, but some pistols use simple blowback or gas operation mechanisms.

The Uzi ( /ˈuːzi/ ; Hebrew: עוּזִי, romanized: ʿûzî; officially cased as UZI) is a family of Israeli open-bolt, blowback-operated submachine guns and machine pistols first designed by Major Uziel "Uzi" Gal in the late 1940s, shortly after the establishment of the State of Israel. It is one of the first weapons to incorporate a telescoping bolt design, which allows the magazine to be housed in the pistol grip for a shorter weapon.

The Uzi prototype was finished in 1950. It was first introduced to Israel Defense Forces (IDF) special forces in 1954, and the weapon was placed into general issue two years later. The IDF supplied Uzis to rear-echelon troops, officers, artillery troops and tank crews, as well as a frontline weapon by elite light infantry assault forces.

In automatic firearms, burst mode or burst-fire is a firing mode enabling the shooter to fire a predetermined number of rounds, usually two or three rounds on hand held weapons to fifty or more rounds on autocannons, with a single pull of the trigger. This firing mode is commonly used in submachine guns and assault rifles. Other types of firearms, such as machine pistols, including the Heckler & Koch VP70 and Beretta 93R also have a burst mode.

The burst mode is normally employed as an intermediate fire mode between semi-automatic and fully automatic, although some firearms lack a "full auto" capability and use a burst mode instead. For instance, the M16A4 (the standard-issue service rifle of the USMC) has, in addition to the semi-automatic mode, a three-round burst mode, which replaced the fully automatic mode of the previous M16A1 and M16A3 models. The reason for this replacement was the massive waste of ammunition and very poor performance of soldiers who fired their rifles in fully automatic mode during the Vietnam War.