Composition
Main article: Musical composition

An old songbook showing a composition
"Composition" is often classed as the creation and recording of music via a medium by which others can interpret it (i.e. paper or sound). Many cultures use at least part of the concept of preconceiving musical material, or composition, as held in western classical music. Even when music is notated precisely, there are still many decisions that a performer has to make. The process of a performer deciding how to perform music that has been previously composed and notated is termed interpretation. Different performers' interpretations of the same music can vary widely. Composers and song writers who present their own music are interpreting, just as much as those who perform the music of others or folk music. The standard body of choices and techniques present at a given time and a given place is referred to as performance practice, where as interpretation is generally used to mean either individual choices of a performer, or an aspect of music which is not clear, and therefore has a "standard" interpretation.

In some musical genres, such as jazz and blues, even more freedom is given to the performer to engage in improvisation on a basic melodic, harmonic, or rhythmic framework. The greatest latitude is given to the performer in a style of performing called free improvisation, which is material that is spontaneously "thought of" (imagined) while being performed, not preconceived. Improvised music usually follows stylistic or genre conventions and even "fully composed" includes some freely chosen material. Composition does not always mean the use of notation, or the known sole authorship of one individual. Music can also be determined by describing a "process" which may create musical sounds; examples of this range from wind chimes, through computer programs which select sounds. Music which contains elements selected by chance is called Aleatoric music, and is associated with such composers as John Cage, Morton Feldman, and Witold Lutosławski.

Music can be composed for repeated performance or it can be improvised: composed on the spot. The music can be performed entirely from memory, from a written system of musical notation, or some combination of both. Study of composition has traditionally been dominated by examination of methods and practice of Western classical music, but the definition of composition is broad enough to include spontaneously improvised works like those of free jazz performers and African drummers such as the Ewe drummers.

What is important in understanding the composition of a piece is singling out its elements. An understanding of music's formal elements can be helpful in deciphering exactly how a piece is constructed. A universal element of music is how sounds occur in time, which is referred to as the rhythm of a piece of music. When a piece appears to have a changing time-feel, it is considered to be in rubato time, an Italian expression that indicates that the tempo of the piece changes to suit the expressive intent of the performer. Even random placement of random sounds, which occurs in musical montage, occurs within some kind of time, and thus employs time as a musical element.

Notation
Main article: Musical notation

Notation is the written expression of music notes and rhythms on paper using symbols. When music is written down, the pitches and rhythm of the music is notated, along with instructions on how to perform the music. The study of how to read notation involves music theory, harmony, the study of performance practice, and in some cases an understanding of historical performance methods. Written notation varies with style and period of music. In Western Art music, the most common types of written notation are scores, which include all the music parts of an ensemble piece, and parts, which are the music notation for the individual performers or singers. In popular music, jazz, and blues, the standard musical notation is the lead sheet, which notates the melody, chords, lyrics (if it is a vocal piece), and structure of the music. Scores and parts are also used in popular music and jazz, particularly in large ensembles such as jazz "big bands."

In popular music, guitarists and electric bass players often read music notated in tablature (often abbreviated as "tab"), which indicates the location of the notes to be played on the instrument using a diagram of the guitar or bass fingerboard. Tabulature was also used in the Baroque era to notate music for the lute, a stringed, fretted instrument. Notated music is produced as sheet music. To perform music from notation requires an understanding of both the rhythmic and pitch elements embodied in the symbols and the performance practice that is associated with a piece of music or a genre.