Cord presentation is the presence of the umbilical cord between the fetal presenting part and the cervix, with or without intact membranes. ( i.e if the cord  is present ABOVE the cervix, with ruptured membranes- this is cord PRESENTATION)

Cord prolapse is descent of the umbilical cord through the cervix  in the presence of ruptured membranes.

Cord prolapse can be occult ( Alongside the presenting part) or OVERT (Past the presenting part)