"Top secret" refers to a classification level used to protect sensitive information that, if disclosed, could cause significant harm to national security or other critical interests. This designation is commonly used by government agencies, such as the Department of Defense or CIA, to safeguard military plans, intelligence operations, and diplomatic communications. Access to top secret information is restricted to individuals with the necessary security clearance. These clearances are granted after thorough background checks and training on handling classified materials. Violating the rules surrounding top secret information can lead to severe legal consequences, including imprisonment.