High fidelity or hi-fi refers to the reproduction of sound and image that is very faithful to the original. Hi-fi aims to achieve minimal or unnoticeable amounts of noise and distortion. The term "hi-fi" can be applied to any reasonable quality home music system. Hi-fi enthusiasts are often known as audiophiles or videophiles.
See also: Lo-fi
High Fidelity is also the title of a book by Nick Hornby about an audiophile and his relationships.