place in which people legally are physically confined and usually deprived of a range of personal freedoms
A prison (also known as a jail or gaol (dated, British and Australian English), penitentiary (American English), detention center (or centre if outside the US), correction center (American English), correctional facility, lock-up or remand center) is a facility in which inmates (or prisoners) are forcibly confined and denied a variety of freedoms under the authority of the state. Prisons are most commonly used within a criminal justice system: people charged with crimes may be imprisoned until their trial; those pleading or being found guilty of crimes at trial may be sentenced to a specified period of imprisonment. In simplest terms, a prison can also be described as a building in which people are legally held as a punishment for a crime they have committed.
Prisons can also be used as a tool of political repression by authoritarian regimes. Their perceived opponents may be imprisoned for political crimes, often without trial or other legal due process; this use is illegal under most forms of international law governing fair administration of justice. In times of war, prisoners of war or detainees may be detained in military prisons or prisoner of war camps, and large groups of civilians might be imprisoned in internment camps.
In American English, the terms prison and jail have separate definitions, though this is not always followed in casual speech. A prison or penitentiary holds people for longer periods of time, such as many years, and is operated by a state or federal government. A jail holds people for shorter periods of time (e.g. for shorter sentences or pre-trial detention) and is usually operated by a local government. Outside of North America, prison and jail often have the same meaning.
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