Universal key fractions (e.g. an A natural in the scale above becomes ) or, more commonly in written text, by inserting an accidental before the number (e.g. the same note becomes 5 or 4). In music theory aimed towards jazz and popular music, all triads are represented by upper case numerals, followed by a symbol to indicate if it is not a major chord (e.g. "m" for minor or "ø" for half-diminished): When representing the triads rooted in a minor key, accidentals are used to indicate the chromatic alteration from the assumed major key roots indicated by numerals that don't have accidentals:
Quarter note Quarter note A quarter note (American) or crotchet (British) is a note played for one quarter of the duration of a whole note (or semibreve). Often, musicians will say that a crotchet is one beat, but this is not always correct, as the beat is indicated by the time signature of the music; a quarter note may or may not be the beat. Quarter notes are notated with a filled-in oval note head and a straight, flagless stem. The stem usually points upwards if it is below the middle line of the stave or downwards if it is on or