Interval (music)
Two notes on a keyboard which are next to one another (counting both white and black notes) are a “semitone” apart. A “tone” is two semitones (see semitone). However, an “intervale” depends on how the notes are written (what they are called) e.g. whether the black note between D and E is written as D sharp or E flat (which are two different names for the same note).