Q. What is a tritone?

A. A tritone is a specific type of interval. It can start on any note, but the interval must be an augmented fourth or diminished fifth (these are the same). For example, if the bottom note is C, the top note will be F# (C to F is a fourth, then one must augment this by a semitone to get to F#). This also works if one thinks of it as a diminished fifth: C to G is a fifth, then make the interval smaller by a semitone to get to the F#. A tritone has also been called 'the Devil in music', and can be recognised in some songs, such as Leonard Bernstein's 'Maria' from "West Side Story".