Revolver-type weapons are part of the long development of making better multishot weapons. They were partly an attempt to improve on pepper-box type weapons, which used a revolving cylinder with one set of firing mechanisms, but had multiple barrels as well. Firing through a single barrel saved the expense and weight of having the multiple barrels of the Pepper-box. Revolvers have remained popular to the present day in many areas, although they have largely been supplanted by semi-automatic magazine-fed pistols such as the Colt 1911, especially in circumstances where reload time and higher bullet capacity is important.
A revolver works by having several firing chambers arranged in a circle in a cylindrical block that are brought into alignment with the firing mechanism and barrel one at a time. A single action revolver requires the hammer to be pulled back by hand before each shot. In a double action revolver, the trigger pull can pull back the hammer as well as release it.
Most commonly, such guns have a five- or six-shot capacity; however, some revolvers have up to a 10-shot capacity (this often depends on the caliber, though different companies produce revolvers in the same calibers with different capacities, due to other design differences), and each chamber has to be reloaded manually. This makes the procedure of reloading such a weapon slow (even with the help of such devices as speed-loaders). The alternatives are a replaceable cylinder, a "speed-loader" which can reload all chambers at once, or a moon clip that holds half or a full load of ammunition and that is inserted along with the ammunition.
Due to the simplicity of design, a revolver is easier to make and has higher reliability than other multi-shot firearms in extreme environments. For these reasons, such guns are the most commonly-owned weapons for personal self-defense and hunting, where their capability to fire powerful ammunition with great accuracy has maintained their popularity.
Famous calibers include the .22 rimfire, .38 Special, .357 Magnum, .44 Special, .44 Magnum, .45 Long Colt. There are many more calibers that were once popular; they were introduced in the era of the "Old West". Many of these are still being loaded and used by devotees. These calibers include the .32-20, .38-40, and the .44-40.
Generally lower ammunition capacity and longer reload times have seen revolvers fall out of favor with most police and military users. Famous military revolvers include the Webley, the Colt Single Action Army and the Smith & Wesson 1917. Many police forces still use revolvers for their hostage rescue units.
Elisha Collier developed a flintlock revolver in 1818, and significant numbers were being produced in London by 1822. Samuel Colt received a patent for his revolver on February 24, 1836 and made the first production model on March 5 of the same year.