CYCO is a project centric music composition language. Each CYCO project is composed of a number of sequential 'sections' corresponding to major divisions of the score. Each section is in turn composed of any number of 'parts'. A part combines an instrument with instructions on what that instrument is to play. There are several types of part, some highly specific such as 'metronome', other more general parts include 'strummer', 'controllers', 'bender' and 'qball' (a kind of recombinant event generator).

CYCO takes a functional approach for time-specification and custom time-cues may be defined. It also provides a rich set of pattern generator types.