A more thorough explanation:

A prisoner is someone who is being held in confinement. This means they are not allowed to leave a certain place, like a prison or jail. Usually, a prisoner is someone who has been convicted of a crime and is serving a sentence in prison. However, a person who has been arrested and is waiting for their trial can also be considered a prisoner.

For example, if someone is found guilty of stealing a car, they may be sentenced to five years in prison. During those five years, they are a prisoner and cannot leave the prison without permission. Another example is if someone is arrested for a crime, like robbery, they may be held in jail until their trial. During that time, they are also considered a prisoner.

Prisoners can be classified as federal or state prisoners. This depends on whether they are in a federal or state prison. Federal prisoners are those who have committed crimes that are against federal laws, like kidnapping across state lines. State prisoners are those who have committed crimes that are against state laws, like stealing a car.