I notice that most of the people here show as 'Active Members' although I show as a 'Member'. Is an active member based on the number of posts you submit or the length of time you are here?
It's based on how many posts you have made on the forum. I have been here a couple of years on and off and some members come back and forth. I guess when you are looking for a deal or advice you come here, and less often when you don't need to.
It depends on the number of posts you have done plus that how often you post and log in to the forum,
I think you will become an active member once you cross the required number to reach there and as you can see in case of @Theo they have already achieved the title of 'well known member'. I guess most forum sites provide these titles to instigate interest in members to achieve these titles by posting more at an early stage besides the other benefits (not sure if any of them available on this forum site or not though).
I'm not sure though, it might be related to how frequently you post, or for how long have you been a member.