Members progress their rank with post count. Each rank has 5 grades with the same requirement. For example, a Recruit requires 1 post to move between grades, and a total of 5 to progress to Marine. As you increase in rank, the number of posts required to progress also increases.
For example, a Zealot requires 40 posts to move between grades, and 200 posts to move to the next rank. The central red bar in each rank tracks your overall progress, and increases for each grade you gain. It's a quick way to see which ranks are higher than others if you don't know the order by their names, and tie the ranks together consistently. Later ranks with insanely high post requirements do look quite different and really stand out.
These ranks are reserved for Anvil Staff and those that work closely with the staff to contribute content for the homepage. Staff Members can be easily distinguished by the distinctive rank banner and the fact they're all listed in the Staff tab on the Member page.
Administrator: Manages the site as a whole and other members of the staff team.
Moderator: Staff members who primarily ensure rules are followed and help members.
Contributor: Staff members who primarily write content for the site and help organize events.