When viewing your User CP or Profile, you'll see these color(s) next to who gave you reputation.
Positive Rep.
Negative Rep
Dark blue
This means the person who gave you rep doesn't have any rep power. If the rep they send you is positive or negative, it doesn't factor in to your rep points. Details below explain why a user can have no rep power.
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Reputation User Spread
How many different users must you give reputation to before you can hit the same person again? 5 users
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Here are most of the reputation factors, explained:
Every new user starts off with a default of 10 reputation points.
If you receive negative reputation from a user, it is multiplied by this factor = 0.5
For every 100 posts, users gain 1 point of reputation-altering power.
For every 50 points of reputation, users gain 1 point of reputation-altering power.
A user must have 50 posts before his reputation hits count on others.
A user must have a certain amount of points before his reputation hits count on others.
The amount of reputation clicks can a user give over each 24 hour period = 10 (admins/mods usually dont have a limit)
The amount of different users must you give reputation to before you can hit the same person again = 5
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Basically, it's pretty simple: The amount of posts you have, longevity on this site, rep you receive & have taken away all factors into your reputation power, which is listed under your Userp CP & Avatar along with your total rep points.
So come on guys post..post...post....post means more points,so get posting to see your karmas grow lol
lol 
not that I'm hinting or anything!!!
I've just got the green blocks and if they chose to leave a comment... doesn't say who they're from.
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