Probably the oddest thing in the Universe.The GuideThe Babel fish is a small, bright yellow fish, which can be placed in someone's ear in order for them to be able to hear any language translated into their first language. Ford Prefect puts one in Arthur Dent's ear at the beginning of the story so that he can hear the Vogon speech. "The Babel fish is small, yellow, leech-like, and probably the oddest thing in the Universe. It feeds on brainwave energy received not from its own carrier, but from| Hitchhikers