You lean something new everyday

Wilhelm scream

The Wilhelm scream is a repeatedly used film and television stock sound effect first used in 1951 for the film Distant Drums. The effect gained new popularity (its use often becoming an in-joke) after it was used in Star Wars and several other blockbuster films as well as television programs and video games.

The Wilhelm scream has become a well-known cinematic sound cliché, and is claimed to have been used in over 140 films, as well as every episode of Primeval.

Read the rest here
Wiki

You learn something new e-v-e-r-y-d-a-y :D