Notation is a set of visual instructions designed to represent musical sound. Notation can take many forms but the method most familiar to western art music has been in a process of continuous development since plainchant was written down in the 9th century. As a language, all notation is necessarily inaccurate since there is no direct visual analog for sound. Asa result, performers have to interpret the notation in order to produce the notation in order to produce the most accurate possible recreation of the composer's intentions.


Historical development

The naming of notes by letters of the alphabet goes back as far as the ancient Greeks; the Romans also possessed an alphabetical system. In both cases, however, this nomenclature served rather the purposes of scientific discussion than those of performance.


An early (7th-century) system of notation was the of neums or neumes, i.e. signs, of which the original generating forms were merely the grave and acute accents plus a horizontal line, but which developed into the elaborate system still in use in the plainsong manuals of the Church. They are now precise (at all events as to pitch), so that an instructed singer can read from them, but for long they were merely approximate in their indications, serving to inform the singer as to which of the plainsong melodies in their repertory they were expected to sing and to remind them of its general melodic curves and rhythms. Our conventional signs for the turn and the trill are derived from details of the neum notation. The present exactitude in the indication of pitch has been effected by adding to the one line of the early neum notation. Plainsong now uses a staff of four lines and other music one of five. The clef derives from the neum notation: attached to the staff it fixes the pitch of one of its lines as middle C or some other note and, one note being thus precisely indicated, all others are likewise decided.


Proportional notation of an exact character (i.e. as to the time values) began in the 10th century when the primitive developments of polyphonic music (as distinct from the previous purely melodic music) brought about its necessity. Definite notes, of different shapes according to their intended proportionate length, were now devised and from them is derived our present series of semibreve, minim, etc. Bar lines became common only during the sixteenth and seventeenth centuries (earliest use 1448): they were at first casually drawn as mere aids to the eye – the idea of making them of equal time-value coming later. Their first use was in choral scoring, the object being to exhibit the coincidence of the different voices; the separate voice-parts for the use of the singers did not, therefore, possess them.


The staff notation has gradually become very elaborate but is still (rationally considered) incomplete and in many ways imperfect. It would appear, however, that if music continues to grow in complexity (use of microtones, for example) the present staff notation must some break down. Certain simple but practical reforms, however, could be pretty easily effected, one example being the adoption of (say) the crotchet (quarter-note) as the invariable beat-value. The only reformed notation that has so far widely established itself is that called tonic sol-fa.