Notes are the musical notation representing a fixed pitch. While the word strictly refers to the physical notation of a pitch, it's more commonly used to refer to both the pitch and the notation. When we're trying to figure out a piece of music, we rarely ask which pitches are being played; we always ask which notes are being played. But if we try to describe a song as having the same note in several places, we're technically wrong. Considering that each note is a separate notation, even if the pitch is the same, it's impossible to have the same note in several places.
Notes are named after the first seven letters in the alphabet -- A, B, C, D, E, F, and G -- and keep the same letter value regardless of the octave. But since there are twelve notes in a diatonic scale, the seven notes can be altered. To get the extra five notes, we sharp (raise by a half-step) and flat (lower by a half-step).
The types of notes and their values are based on the amount of time they take up in a song.
Whole notes (or breve notes) are four beats, which is equal to one measure in 4/4 time. They are represented by a hollow, oval note with no stem.
Half notes (or minim notes) are half of a whole note, or two beats. They are written as a hollow note with a stem that points up when placed below the middle of the staff, up when placed above it.
Quarter notes (or crochet notes) represent a quarter of a whole note, or one beat in 4/4 time. They are the most recognizable note: a solid black note with a stem.
Eighth notes (or quaver notes) are one-eighth of a whole note and are written exactly like a quarter note, but with a flag attached to the stem. When more than one eighth note is placed side by side, a solid beam connects the adjacent notes.
Sixteenth notes (or demiquaver notes) are one-sixteenth of a whole note and represented as an eighth note with two flags or two solid beams.
Thirty-second and sixty-fourth notes represent the section of a whole note indicated by their names; they are drawn as eighth or sixteenth notes with an additional flags.
It's also important to mention that a note's value can be changed by adding a dot. Dotted notes represent the value of the original note, plus one half. For instance, dotted half notes are held for three beats, dotted quarter notes for a beat and one half, and so on.
