Points can determine what you can and can't do on the world, the lower points a player has the less trustworthy of abiding by the rules they are.
Points can be deducted for rule violations, if you see a player with less than 5 points it means they have at some point broken rules on the server but have not been banned.
A player with more than 5 points can be deemed quite trustworthy. A player with 6 points has normally played on the server for quite some time and a player with more than 6 points has carried out some good deeds for the entire community (such as helping new players, hosting community events, plus more)