The smallest standard distance between any two given notes in the West, is the semitone.   The semitone can be found between any two adjacent keys on the piano.  In other words, take any key on the piano and go to the note immediately above or below it.

The whole tone is the distance of two semitones.

On the guitar, the distance of one fret is a semitone or a half step.  A whole tone or tone is the distance of two frets.

Since most web browsers don’t support specialized music fonts, you will often see a lower case “b” used to represent a flat (for example, Gb).  The sharp will sometimes be symbolized with a number sign “#” (for example, G#).  A double sharp is represented with an “x” (for example, Gx). The double flat is indicated with two lower case b’s  such as: “bb” (for example Gbb).

Enharmonic Equivalents

Enharmonic equivalents are notes that sound the same but are written with different letter-names.  For example, the F# and Gb are both found on the 2^nd fret of the sixth string and sound identical.  G# and Ab both share the 1^st fret of the third string.  Context determines whether a note should be called an F# or a Gb.  Here are some other notes you should know about:

Now let’s apply this to the guitar…

Understanding Sharps and Flats on the Guitar Part 1