What is a Junior Member, Member etc?

[alc3261]

This may be a stupid question but I cannot find the answers - I've tried FAQs and Search.
What do the various designations mean and what do you have to do to go up a level?
Is it related to duration of membership, number of posts, something else??

[85AKbN]

00-29 posts: junior member
30-99 posts: member
100 + posts: senior member

[heath]

While we're asking here, what are the green blocks below the member class. I'm a senior member with one, Mr. Darkside himself has three.

[KrazyIvan]

While we're asking here, what are the green blocks below the member class. I'm a senior member with one, Mr. Darkside himself has three.

See this thread: http://fpgeeks.com/forum/showthread.php/5273-What-does-quot-Rep-Power-quot-mean?highlight=power