The Ordo details those changes which arise due to the interaction of the Temporal and Sanctoral cycles. In addition the Ordo contains detailed information concerning the celebration of the various classes of Votive Masses,e.g. Masses of External Solemnities, rubrics for the Forty Hours.
The Ordo follows the format of the Roman Ordo that was produced for the Universal Calendar in the late 1930's following the fifth editio post typicam of the Roman Missal that was promulgated by SRC in 1939.
The Ordo is written entirely in Latin.