If you've seen an action movie in the last twenty years, then you've heard it. You've probably even joked about it. This infamous scream has appeared in all of the "Star Wars" and 'Indiana Jones" films along with "The Two Towers." Yes, it has a name. It's called the Wilhelm Scream.

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The Wilhelm Scream is probably the most iconic sound effect in the history of film. Back in 1951, a series of screams were recording for the Warner Brothers film "Distant Drums." They were used in a scene where a man is attacked (and possibly has his DICK bitten off, Blog hasn't seen the movie) by an alligator. The recording was later tucked away in the studio's archives.

"Star Wars" sound designer Ben Burtt tracked down the scream recording - which he named "Wilhelm" after a character who let out the same scream in a film called "Charge at Feather River." Ben has since adopted the scream as sort of a personal sound signature. He and a small circle of sound effects people keep it in steady rotation. Most recently, the scream was used in "Confessions of a Dangerous Mind" and "Once Upon a Time in Mexico."

And now you know.