This document discusses prisons and jails in the United States criminal justice system. It notes that prisons are state or federal facilities that incarcerate adults sentenced to confinement, while jails are local facilities that hold individuals pending trial or sentencing or for shorter sentences. The document also discusses the large racial disparities in US prison populations, with incarceration rates for African American males being much higher than for Caucasian males. It outlines different security levels in prisons from minimum to maximum security and classification systems used to determine custody levels. The growth of prison and jail populations is also summarized due to "get tough" sentencing policies like three strikes laws.