What is the difference between owners, viewers, description contributors and reviewers?

Argos DMP / other research plan owner is the person initiating the DMP. People who are invited to join the wirting process are members. Owners have extra editing rights and they are the ones to finalize the DMP / other research plan. Viewers can only preview the DMP and other research plans. Description contributors can only edit the description(s) and reviewers can only comment in the different parts of the Plans.