"It's a Babel fish."

The Babel fish is a handy literary device that allows Arthur Dent to understand anything said by any creature from an alien race, thus saving time describing translator devices or aliens gabbling incomprehensibly in some bizarre tongue.

Its name recalls the biblical story of the tower of Babel, a myth which offers one explanation for the variety of different languages on Earth.

Babel Fish is a website run by Yahoo that automatically translates text into other languages.