The Miranda Warning is a police warning which is given to criminal suspects who are in the custody of law enforcement in the United States before they can ask questions regarding what took place during the crime.
Law enforcement can only ask for specific information such as name, date of birth and address without having to read the suspects their Miranda warnings. Confessions and other information that you provide them will not make up admissible evidence unless you have been made aware of and waived your "Miranda rights."
The Miranda warnings were mandated by the 1966 United States Supreme Court decision in the case of Miranda v. Arizona as to protect a criminal suspect's Fifth Amendment right to help avoid self-incrimination during police interrogation. This was once referred to as undergoing the ‘third degree.’