Definition of Security classification:
Security level assigned to a government document, file, or record based on the sensitivity or secrecy of the information. Four common security classifications are: (1) Top secret: Highest degree of protection for information that is paramount in national defense matters and whose unauthorized disclosure may cause extremely grave danger or damage to the nation. (2) Secret: Unauthorized disclosure of which may result in serious damage or danger. (3) Confidential: Unauthorized disclosure of which may undermine the defense or government operations. (4) Restricted: Unauthorized disclosure of which is undesirable.
Meaning of Security classification & Security classification Definition