U.S. Air Force pilots with the Thunderbirds perform the calypso pass maneuver in F-16 Fighting Falcon aircraft during a practice session prior to the Gunfighter Skies air show at Mountain Home Air Force Base, Idaho, September 19 and released September 24, 2014. (Photo by Tech. Sgt. Manuel J. Martinez/Reuters/US Air Force)

The photographer holds up a Samsung Galaxy Tab 7.7 tablet at the Samsung hall at the IFA 2011 consumer electonics and appliances fair the day before the fair's official opening on September 1, 2011 in Berlin, Germany. The IFA 2011 will be open to the public from September 2-7. (Photo by Sean Gallup/Getty Images)

Young man making the O.K. sign. (Photo by George Marks/Retrofile/Getty Images). Circa 1950s