DCO - it can also be called DCD, just DC or CEA or VEA - one of the key concepts of the system - is a double or triple-authenticated Art Object - high resolution print, on archive paper or a waterproof, matt white, paper-like substrate, A4 (297 x 210 mm) (come to think of it, it could also be laser-etched on zirconium, it is, after all a one-off output of a digital file.

Since 2022 those Art Objects come in two flavours:
›Counted Edition - the image will evolve over time, but those changes are minor, non-essential, the Buyer can personalise it by adding their own data or picturial elements.
›Versioned Edition at each issue the artwork is re-imagined, the Buyer can participate - from adding elements to discussing, arranging and re-creating all - in as much as it is practicable.

See also:
›What is the difference between Counted Art Edition (CE) and Versioned Art Edition (VE) ?