Dance music

Irish dance music is fast, in binary or ternary time, with a simple structure. In principle, there are one or two sharps; the keys of D and G are by far the most common. Other keys (A, C, b minor) exist but are less widespread. The range rarely exceeds the first 2 octaves.

There are several types of tunes in Irish music: jigs and reels are most common, followed by hornpipes, and then other types of tunes such as polkas, slides, and set dances, slip jigs and waltzes (In O'Neill's collection, for example, there are 367 jigs, 349 reels, hornpipes and 149 today, the reels are even more common than jigs; according irishtune.info, 42% of the songs played are in session reels )

Structure 

Because it is an orally transmitted music, retained in memory, its structure is quite simple. In general, tunes are in two parts of 8 bars each, arranged in a "question-answer" pattern. The structure is symmetrical: each part is repeated, then the whole tune is repeated (it is customary today to play tunes at least 3 times). Tunes are arranged in sets of 2 or 3 tunes or more.

Characteristics of Irish Music

• It is a fast dance music, with slower tunes, airs, in the minority.

• The music is transmitted orally and retained in memory. Written traces (sheet music, ABC) are used only as aids to memory, and records of performances.

• Because it is an oral music, it is more fluid than music based on written scores. Often, a tune exists in several different versions; variations are common, the tunes change in transmission and the music becomes the product of the community rather than a composer: the production of many hands.

• The music is taught and transmitted more by example than by formal instruction; we learn by imitation and often the concepts learned are not intellectualised.

• It is of rural origin, and a large part of the repertoire was current in the 18th and 19th centuries.

• Solo performance is at the heart of the tradition, but today the music is often played in groups or sessions. Instruments are played in unison, without harmonies, and the harmonic accompaniment is simple .

• It has a social function, and most musicians are amateurs and play for recreation in informal sessions.

Source : ITMA (Irish Traditional Music Archive)