Concealed carry in the context of Open carry in the United States

Defensive gun use (DGU) is the use or presentation of a firearm for self-defense, defense of others or, in some cases, protecting property. The frequency of incidents involving DGU and their effectiveness in providing safety and reducing crime are controversial issues in gun politics and criminology, chiefly in the United States. Different authors and studies employ different criteria for what constitutes a defensive gun use which leads to controversy in comparing statistical results. Perceptions of defensive gun use are recurring themes in discussions over gun rights, gun control, armed police, open and concealed carry of firearms.

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".

Gun laws and policies, collectively referred to as firearms regulation or gun control, regulate the manufacture, sale, transfer, possession, modification, and use of small arms by civilians. Laws of some countries may afford civilians a right to keep and bear arms, and have more liberal gun laws than neighboring jurisdictions. Gun control typically restricts access to certain categories of firearms and limits the categories of persons who may be granted permission to access firearms. There may be separate licenses for hunting, sport shooting, self-defense, collecting, and concealed carry, each with different sets of requirements, privileges, and responsibilities.

Gun laws are usually justified by a legislature's intent to curb the usage of small arms in crime, and to this end they frequently target types of arms identified in crimes and shootings, such as handguns and other types of concealable firearms. Semi-automatic rifle designs which are derived from service rifles, sometimes colloquially referred to as assault rifles, often face additional scrutiny from lawmakers. Persons restricted from legal access to firearms may include those below a certain age or those with a criminal record. Firearms licenses to purchase or possess may be denied to those defined as most at risk of harming or murdering themselves or others, persons with a history of domestic violence, alcohol use disorder or substance use disorder, mental illness, depression, or those who have attempted suicide. Those applying for a firearm license may need to demonstrate competence by completing a gun safety course and/or show provisions for a secure location to store weapons.

Concealed carry, or carrying a concealed weapon (CCW), is the practice of carrying a weapon (such as a handgun) in public in a concealed manner, either on one's person or in close proximity. CCW is often practiced as a means of self-defense. Following the Supreme Court's NYSRPA v. Bruen (2022) decision, all states in the United States were required to allow for concealed carry of a handgun either permitlessly or with a permit, although the difficulty in obtaining a permit varies per jurisdiction.

There is conflicting evidence regarding the effect that concealed carry has on crime rates. A 2020 review by the RAND Corporation concluded there is supportive evidence that shall-issue concealed carry laws, which require states to issue permits to applicants once certain requirements are met, are associated with increased firearm homicides and total homicides. Earlier studies by RAND found that shall-issue concealed carry laws may increase violent crime overall, while there was inconclusive evidence for the effect of shall-issue laws on all individual types of violent crime. A 2004 literature review by the National Academy of Sciences concluded that there is no link between the existence of laws that allow concealed carry and crime rates.