Over/under is simply the total points in a game. For example if the over/ under for the celtics vs sixers game tonight was 200, you would bet the total of both teams would be more or less than 200. So if the final score 101 to 100 and you bet the over, you would win the bet.

A parlay means all the teams you choose must win, or the parlay is a loser. Say you like the patriots (-14), Cowboys (-10). You parlay them together as 1 bet. Both teams must cover the spread for you to win. The benefit is you get better odds the more teams you parlay. $100 parlay would pay $240. A $100 4 team parlay would pay $1000...

I may try this out later just for fun. I already have several sports book accounts. I am a little skeptical about this, as i always am when someone is giving out "free" money. Even if its only 10 cents. Not sure how secure you personal information would be. Before i wager with a sports book, i always check them out at sportsbook review, which is a rating service for sports books. Then I only use the A rated books.

FYI i have found a very good, highly rated poker site that basically is giving away free money in the form of freerolls. They have 2 $300 freerolls a day that only take about an hour to play all the way through, and pays out 600 places on a sliding scale.