The exact nature of parole varies from jurisdiction to jurisdiction. In the United States, courts may specify in a sentence how much time must be served before a prisoner is eligible for parole. Some states permit sentences of life imprisonment without the possibility of parole; other states do not, and any prisoner not facing the death penalty will eventually have the right to petition for release. In the United States federal justice system, there is currently no possibility of parole for any sentence.
Parole (French, meaning "speech") is also a linguistic term used by Ferdinand de Saussure which, as opposed to langue, describes language in use rather than language as a system.