Traditional Celtic music is played in various forms and can be classified variously as follows:
Classification by context 
- Set dances (dance solo) can be jig or reel. (Table dance:Footed on a tabletop).
- Group dances
- Listening pieces
Classification by musical structure 
- Reels: Tend to be played very fast and usually consist of continuous eighth notes written in 4/4 time
- Jigs: Much slower than reels, jigs usually have eighth notes in 6/8 time with accents falling on first and fourth beats.
- Doubkle jigs
- Slip jigs
- Hornpipe: Similar to reels but more slowly, They are usually written in 4/4 and often played without accents
- Waltzes: Played in a "waltz pace"; Written in 3/4 time and use triplet rhythmn.
- Strathspeys: Dotted rhythms; usually associated with Scottish playing, Cape Breton and Boston fiddle. Utilizes the "Scottish snap". Browns of Kincardie; Cummingses of Freuchie.
- Hornpipes: Derived form pipcorn (stockhorn) Chaucer mentions in Romaunt of the Rose, 1260. 3/2, originally, now 4/4
<ref.Robin WIlliamson|Eng Welsh Scot & Irish Fiddle Tunes|oak Publ|197</ref> Sharp keys are favored but some tunes are in C/Aminor or Fmajor. D, G and A are quite popular, in that order.