When playing music there a few musical terms we need to know before we start because they are used all the time and if we don’t know what they mean we can get confused really quickly.
Semitone – A semitone is the smallest interval that can be played on the piano. This is the distance of 1 note, for example if we take the note C, a semitone above C is C# and the semitone below C is B. If we want to measure the distance from C to D we have gone up 2 notes, C to C# then C# to D so we say that the interval from C to D is 2 semitones. A semitone is also sometimes referred to as a half step or half tone.
Tone – A tone is the interval of 2 semitones. So if we take our C and go up 2 semitones we get to D. Rather than saying that the distance from C to D is 2 semitones we say that the distance from C to D is a tone. If we go down a tone from C we get to Bb. A tone is also sometimes referred to a whole step.