What is it? I can't find any info?

Is it by the post (activity) count?
Or, by time?
Or, by post count and time?

All the main ranks that can be handed out to normal users are: Brand New, Newbie, Jr. Member, Member, Full Member, Sr. Member, and Hero Member.
In addition to the main rankings, there are also sub-rankings that can be applied, and those are: SCAMMER, Donator, and VIP.
Finally, staff sub-rankings are as follows: Staff, Moderator, Global Moderator, Administrator, and Founder.

Rank	Description	Tag
Brand New:	0 posts, gets 1 gold coin under his name.
Newbie:	(none), gets 1 gold coin under his name.
Jr. Member:	1 post written over 4 hours ago, gets 1 gold coins under his name.
Member:	Activity: 15, gets 2 gold coins under his name.
Full Member:	Activity: 60, gets 3 gold coins under his name.
Sr. Member:	Activity: 200, gets 4 gold coins under his name.
Hero Member:	Activity: 400, gets 5 gold coins under his name.