Difference between state and federal jail?

"JAIL" is a Word and a description that the general public loosely applies to most correctional/penal institutions. However - "JAIL" refers to confinement facilities operated by larger cities and counties. STATE PRISONS, are penal institutions operated by the state prison system and which house felony prisoners (and some misdemeanants) convicted in the state courts for breaking state law. FEDERAL PRISONS house prisoners convicted of breaking Federal law and are operated by the US Bureau of Prisons.