TSA Pre allows passengers to provide information about themselves to the TSA prior to their trip. If the TSA determines you're eligible for the program, information about you will be stored in a special bar code on your boarding pass. Once scanned, the code will permit you to skip to an expedited screening line, where the removal of shoes, belts and outer clothing will no longer be required.
There are a few catches however. First, the airline you're flying must be participating in the program. At the moment, American Airlines, Delta, US Airways, United Airlines and Alaska Airlines all participate in some cities, but TSA will expand the program as more airports come in compliance. Second, there is no guarantee that once you're approved you'll be exempt from more thorough screening; random screenings will persist. More information on the program and its requirements is available at this website, www.globalentry.gov.
