The User Reputation system allows forum members to leave comments about one anothers' posts, and thereby contribute to their overall 'reputation' of the forum member. User Reputation in its simplest form is a ranking of your user's benefit to your forum. Users gain and lose reputation based on how their posts are scored by other forum participants. Users with the ability to affect reputation, will either give or take aways points by approving or disapproving with a post's content. You will see the following icon near every post and clicking the icon will launch Popup which will give you couple of options I approve I disapprove As well as have the option of leaving the comment on the post. The amount of Reputation you pass on to other member's also depends on your reputation power which is visible near all the posts. This is a very good question and is added into the FAQ as well - http://www.go4expert.com/faq.php?faq=vb_board_usage#faq_reputation_power
