Celtic music is a broad grouping of musical genres that evolved out of the folk musical traditions of the Celtic people of Western Europe.[1][2] It refers to both orally-transmitted traditional music and recorded music and the styles vary considerably to include everything from "trad" (traditional) music to a wide range of hybrids.

Celtic music means two things mainly. First, it is the music of the peoples identifying themselves as Celts. Secondly, it refers to whatever qualities may be unique to the musics of the Celtic Nations. Many notable Celtic musicians such as Alan Stivell and Paddy Moloney[3] claim that the different Celtic musics have much in common.[1][2][4] These common melodic practices may be used [4] widely across Celtic Music:

Often the melodic line moves up and down the primary chords in so many songs. There are a number of possible reasons for this:
Melodic variation can be easily introduced. Melodic variation is widely used in Celtic music, especially by the pipes and harp.
It is easier to anticipate the direction that the melody will take, so that harmony either composed or improvised can be introduced: cliched cadences that are essential for impromptu harmony are also more easily formed.
The relatively wider tonal intervals in some songs make it possible for stress accents within the poetic line to be more in keeping with the local Celtic accent.
Across just one Celtic group.
By more than one Celtic language population belonging to different Celtic groups.

These two latter usage patterns may simply be remnants of formerly widespread melodic practices.

Often, the term Celtic music is applied to the music of Ireland and Scotland because both lands have produced well-known distinctive styles which actually have genuine commonality and clear mutual influences. The definition is further complicated by the fact that Irish independence has allowed Ireland to promote 'Celtic' music as a specifically Irish product. However, these are modern geographical references to a people who share a common Celtic ancestry and consequently, a common musical heritage.

These styles are known because of the importance of Irish and Scottish people in the English speaking world, especially in the United States, where they had a profound impact on American music, particularly bluegrass and country music.[5] The music of Wales, Cornwall, the Isle of Man, Brittany, Galicia, Cantabria and Asturias (Spain) and Portugal are also considered Celtic music, the tradition being particularly strong in Brittany, where Celtic festivals large and small take place throughout the year, and in Wales, where the ancient eisteddfod tradition has been revived and flourishes. Additionally, the musics of ethnically Celtic peoples abroad are vibrant, especially in Canada and the United States. In Canada the provinces of Atlantic Canada are known for being a home of Celtic music, most notably on the islands of Newfoundland, Cape Breton and Prince Edward Island. The traditional music of Atlantic Canada is heavily influenced by the Irish, Scottish and Acadian ethnic makeup of much of the region's communities.[6] In some parts of Atlantic Canada, such as Newfoundland, Celtic music is as or more popular than in the old country. Further, some older forms of Celtic music that are rare in Scotland and Ireland today, such as practice of accompanying a fiddle with a piano, or the Gaelic spinning songs of Cape Breton remain common in the Maritimes. Much of the music of this region is Celtic in nature, but originates in the local area and celebrates the sea, seafaring, fishing and other primary industries.