In 1955, Harley Clarkwas a cheerleader at the University of Texas when he introduced a hand signal that would become one of the most recognizable signs in college athletics.

At a pep rally, Clark displayed his index and pinky fingers extended, with his two middle fingers tucked under his thumb.

Over the years, "Hook 'em Horns" spread faster than a Texas wildfire and became a symbol for the school and for Longhorn athletic teams.

In a 2006 Associated Press interview, Clark said he wanted a hand signal for the Longhorns that could compete with rival Texas A&M's "Gig 'Em."

That signal — a closed fist with the thumb pointing straight up — dates to the 1930s.

Clark says his friend Henry Pitts showed him the Longhorn sign, which Pitts had made up while shadow casting.

In the AP interview, Clark said the sign was "perfect" and that it "just says Texas."

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