The tunes usually have an A and a B part (sometimes a C,D and a F part).

The A part consists of phrase that gets played twice - followed by the B part that gets played twice.

The A and the B part are repeated - usually three times - and and that is the end of that tune - then the session will go into another tune.

Mostly there are two or three tunes played together and this is known as a set.

The tunes in a session set - are usually the same type of tune i.e. a set of jigs, reels, polkas, hornpipes etc.