When you hover over the "Thanks" link you get...
View attachment 142745
Depending on the selection, the first three (from left) is weighted at 1 point each and the latter three is neutral (zero points). It can be set to negative or a custom score.
A certain amount of "points" will get you to a "trophy" level according to this chart...
You can earn trophies by carrying out different actions. This page shows a list of the trophies that are available.
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If the trophy function was disabled, the point system will work to elevate a user title ladder; new member, member, active member, or well-known member.