Generally, a juvenile, sometimes called a minor, is a young person. In the legal context, a juvenile is a person below the age at which an ordinary criminal prosecution is permitted (in most countries, this is between the ages of 12 and 18).
The law typically gives juveniles special protections such as keeping their name confidential when they are accused of a crime, and requiring a parent or legal guardian to be present during police questioning. Furthermore, in many jurisdictions, crimes committed by juveniles are tried in a separate juvenile court. The criminal justice system may also treat juveniles more leniently than adult criminal offenders. For example, a juvenile may be charged and tried as an adult for a murder, but he may not be subject to the death penalty in some jurisdictions because he is a juvenile, and is usually not incarcerated (=to put or keep someone in prison, a place used as a prison or an enclosed place and to prevent them from leaving it) with adult prisoners.