Here's what Rob pasted when he answered this question a while ago:
"The following is an explanation that Ryan, the site founder put up:
EHelp.com is a reputation based community. You can gain reputation scores by asking quality questions (clear and useful) and posting helpful answers. When other users vote your question or answer up, you will receive 5 points of reputation, but when they vote it down, you'll lose 2 points. If your post gets removed by the moderator/reputable users, you'll lose 20 points."