When the public thinks of airport security, they often immediately think of the Transportation Safety Administration (TSA) putting in place measures or barriers to prevent malicious individuals from either getting through airport security or, if the individual happens to make it through the security checkpoint, perpetrate a crime – e.g., hijacking – while on the plan. Measures such as locked cockpits enhanced screenings, and identification document requirements (e.g., the Real ID Act in the United States) are some measures that have been taken since the terrorist attacks on 9/11 to strengthen airport security.