There are many unique terms associated with sports wagering. Bookmark our glossary of betting terms and use it as a reference if you come across an unfamiliar word or phrase while placing bets.
Accumulator: A parlay bet in North America, accumulator wagers consist of two or more selections and each side must win (or push) to create a winning ticket.
Action: Any live wagering option or the total amount wagered on a specific event. Bookmakers accept action on all posted betting odds.
Across the board: Three horse racing bets that cover a horse to win, place and show.
Added game: Appear on betting boards after main lists are posted. They are common in college football and mainly appear due to public demand. An added game may also be a postponed match, like a rainout in baseball, from the previous day.
AET odds: After extra time (AET) odds are posted primarily on soccer matches when extra time is added at the end of regulation time due to in-game stoppages. AET odds are offered as live betting options.
Also ran: An athlete, horse, or greyhound that doesn’t finish in a paying position during a race.
Alternate lines: Odds that are higher or lower than the main posted line. Common with point spread and game total betting in basketball and football.
American odds: American odds are in a “big three” group that also includes fractional and decimal odds. American moneylines posted at (-110) are the same as 1.91 decimal odds and 10/11 fractional pricing. All three formats return a $100 profit on a winning $110 wager.
Ante-post: Futures odds on horse and greyhound races that are posted at least one day prior to a race. Ante-post odds are common on Triple Crown races like the Kentucky Derby.
Arbitrage: Often shortened to ARB, arbitrage wagering is a betting style where all possible outcomes of a single game are covered. ARB betting options are rare and arise when sportsbooks have varying opinions on the proper odds for a match.
Asian handicap: Most common in soccer, Asian handicap odds start at 0.25 goals and can go as high as 2.0 goals. These are two-way bets since a draw/tie option is not offered.
ATS: Against the spread odds (ATS) are designed to create equal action on both sides of a competition. Bettors may have a choice between Las Vegas as a -3.5 point ATS favorite at home versus Denver as a +3.5 point underdog on the road.
Australian Open: First of four women's and men's Grand Slam tennis tournaments that are played over two weeks in mid-January.
Backdoor cover: Occurs when a score helps bettors cover a spread bet but doesn’t affect the game winner. If Baltimore is up 35-21, as a -10 point favorite, Cleveland bettors earn a backdoor cover if the Browns score a late touchdown to make the final score 35-28 in favor of the Ravens.
Bankroll: Money set aside, or deposited into an account, that is used for betting. A player’s bankroll increases with each winning wager and decreases with each losing bet.
Bankroll Management: Much like managing a personal bank account, bettors should practice proper bankroll management. Setting wagering limits, shopping for the best odds value, plus only wagering what one can afford to lose, are keys to properly managing a sports betting budget.
Beard: A bet runner who places wagers for professional bettors so they can conceal their identity from bookmakers.
Belmont Stakes: Third jewel in the Triple Crown of thoroughbred racing. Race day is the first or second Saturday in June (three weeks after the Preakness Stakes) at Belmont Park in Elmont, New York.
Bet: Any wager involving money wagered at a sportsbook, casino, racebook or poker room.
Betting exchange: A middleman that isn’t a sportsbook or a bettor. An exchange posts bets with two sides and the betting option remains listed until both sides are bet on. Betting exchanges profit by taking a small commission (juice) from winning tickets.
Betting strategy: Various plans that bettors use to get a leg-up on bookmakers. Primary betting strategies should include proper bankroll management and performing extensive research prior to placing wagers.
Book: Short for a bookmaker or sportsbook that posts odds and accepts bets.
Bookie: Short for a bookmaker.
Bookmaker: A licensed individual who sets daily betting odds and accepts bets. Also known as a linemaker.
Breeders’ Cup: Grade I thoroughbred championship horse racing series that runs on the first Friday and Saturday in November. The series is run at a variety of race tracks. Santa Anita Park and Churchill Downs have hosted the most Breeders' Cup events.
Buy points: Bettors can buy points, using alternate point spreads and game totals, to gain a more favorable line. If a spread is set at +2.5 points a player can buy one point to move the line up to + 3.5 points. Juice attached to the odds increases with each point purchased.
Calder Cup: Awarded to the top-performing rookie player during the NHL regular season.
CFP: College Football Playoffs, which determine the NCAA football National Champion.
Chalk: Another term for favorite. Los Angeles is the chalk side if the Lakers are a -3 point favorite over the Houston Rockets.
Chalk bettor: A player that bets on favorites with the majority of their wagers
Circled game: Matches that have set betting maximums, which are capped at low amounts. Games are usually circled when bookmakers face unknowns such as player injuries, weather or rumors that surface prior to a match. Opening odds and prop options are often circled as well.
Closing line: The final betting odds posted prior to the start of a competition.
Co-favorite: Two or more sides with identical odds to win. Common with futures odds, bookmakers may post co-favorites to win the NBA Finals championship.
Combine: A series of fitness tests that help scouts from professional teams evaluate amateur athletes. The NFL Scouting Combine is a highly anticipated prelude to the annual NFL draft.
Commission: Another term for vigorish and juice, commission is the bookmakers take on any bet. It is also the amount a betting exchange takes from winning wagers.
Commissioner’s Trophy: Awarded annually to the MLB World Series champion.
Correct score: Bettors are offered a list of possible final scores on a match. In soccer, players can bet on a match ending as low as 0-0 or as high as 5-0 plus all scores in between. The most likely result is the favorite and the least likely result is the underdog.
Cover/Covering the spread: Any bet where a favorite wins and the final score exceeds the point spread. New England winning 32-21 over Miami means the Patriots would cover a -10 point spread. If the Pats win 29-21 they don’t cover the spread and bets are graded as losing wagers.
Decimal odds: Common in Europe, decimal odds are in a “big three” group that also includes fractional and American odds. A 1.91 decimal line equals -110 in American odds and 10/11 in fractional pricing. All three formats return a $100 profit on a winning $110 wager.
Dog: Short for underdog, a dog is perceived as the least likely side to win and is tagged with plus pricing. Atlanta would be a dog if the Braves moneyline is set at +125 and the Houston Astros are posted with -120 odds in baseball.
Double action: Also known as an “If bet” a double action bet automatically takes the stakes and/or winnings from a successful wager and places that amount on a second betting option.
Double bet: A betting amount that is double a bettor’s normal wager. Bettors often double their bet when they feel one side is vastly superior to another.
Double result: A single betting option that combines the score of a game at halftime and the score at the end of the same game.
Double-header: Two games that are played back-to-back on the same day. Most common in baseball, a double-header will often take place if a game from the previous day was rained out.
Draw: Any contest where the final score ends in a tie. In most instances, a draw is graded as a PUSH and original bet amounts are returned. A key exception is three-way lines that offer tie/draw as one of three betting options.
Drift: Betting odds that grow longer after the opening line is posted. A moneyline that moves from +220 to +225 to +230 is said to be drifting.
Each-way: Common in horse racing, each-way betting takes a single amount and splits it on a horse to finish first or second. Both bets pay if the horse finishes first while just one bet pays if the horse finishes second. The return on a first place win is always higher than the return on a second place win.
Edge: Gaining an advantage through extensive research or having insights that are not publicly known.
EPL: English Premier League is the top ranked football association in the United Kingdom.
Even money: Odds that return the exact amount of the original bet. A $100 bet on Fractional (1/1) American (+100) or Decimal (2.0) odds would return a $100 profit.
Exotic Bet: Betting options beyond point spreads, moneylines and game totals. Proposition bets, specials and parlays are the most common types of exotic bets.
Exposure: Amount of money a bettor or bookmaker stands to lose on any given wager.
Favorite: Any side priced with a negative number. San Francisco (-360) would be the moneyline favorite over Arizona (+280) in an NFL matchup.
FIFA World Cup: Played every four years, the World Cup championship is the most watched soccer tournament on the Planet. The World Cup is slated to be played in the US, Canada and Mexico in 2026.
Final Four: Most commonly refers to the last four teams remaining in the NCAA March Madness basketball tournament. Two Final Four games are played prior to the National Championship game.
First half bet: A wager that focused on the result of the first half in sports like basketball, soccer and football. The most popular first half betting odds are spread, moneyline and game total options. A variety of team and player props are also offered as first half bets.
First/Last/Anytime Scorer: Offered on many sports, these are three pre-game prop betting options. In the NHL, all skaters will have odds on whether they score the first and/or last goal, plus whether they score at any point during a game.
Fixed odds: When a wager is placed, and a bookmaker accepts it, the line becomes fixed odds. If a bet is placed on Las Vegas at +3.5 odds and the line moves down to +3.0 prior to the game, players who purchased the Raiders at +3.5 retain the previously accepted fixed odds. Also a term for moneyline odds.
Fractional odds: Common in the UK, fractional odds are in a “big three” group that also includes Decimal and American odds. A fractional line of 10/11 equals -110 in American odds and 1.91 decimal pricing. They each return a $90.91 profit on a winning $100 bet.
French Open: Second of four women's and men's Grand Slam tennis tournaments that are played over two weeks in late May and early June.
Futures bet: A wager placed on an event that will take place in the near or distant future. Betting on the winner of the Super Bowl, Stanley Cup, NBA Finals and World Series are popular futures options. Futures are also offered in soccer, major horse races, plus golf and tennis tournaments.
Game total bet: Over/Under betting on how many goals/points/runs will be scored in a game. If a baseball game total is set at 7.5 runs, bettors need to decide if the combined total runs in that contest will be over or under eight runs.
Graded Bet: A wager that bookmakers officially mark as a winner, a loser, or a push, once a competition has ended. Winnings, or push refunds, are paid out after a bet has been graded.
Grand Salami: Bookmakers offer Over/Under odds on the total goals/runs/points scored in all of the games, from a specific league, on any given day. If there are seven games on the NFL schedule, the line may be set at 36.5 combined goals with -110 on both sides as the most common juice.
Half ball handicap: Soccer betting odds where 0.5 goals, plus or minus, is the point spread.
Half time bet: Wagers placed on the outcome of just the second half of a competition. Half time bets can be placed during intermission or as live wagers once the second half begins.
Handicap: Betting odds set by a bookmaker that are designed to level the playing field. New Orleans may have a -7.5 point handicap, before or during the game, when they play a perceived weaker Atlanta squad. If the Saints win by eight or more points - they cover the handicap and produce winning wagers.
Handicapper: A bettor who researches matchups and then places a bet. Also applies to tipsters who publish predictions on various sporting events.
Handle: Total amount of money a bookmaker accepts on a single game or event. The total handle bet on Super Bowl 54 in Nevada was $154.7 million. Bookmakers earned an $18.8 million profit when Kansas City completed a come-from-behind win over San Francisco.
Hart Trophy: Awarded to the most valuable player during the NHL regular season.
Hedge: Most common with parlay betting and as a risk management tool. Hedging a bet consists of betting on the opposite side of an original wager to set up a guaranteed return. A hedge bet may also be placed to reduce the initial risk on a potential losing wager.
Holding your own: A bettor who is on a streak where they aren’t winning or losing but rather just breaking even on a series of bets.
Home field advantage: The perceived benefit a team gains when playing in familiar settings at their home stadium.
Hook: A half point added to point spreads and game total odds. A hook guarantees a wager will not be graded as a push. One side will win and one side will lose.
If bet: A member of the parlay family, an If Bet consists of two or more wagers. On a two-team if bet, a player applies the stake and/or profit of a winning wager as a bet on a second game if the initial wager is successful.
In play betting: Wagers placed after an event after it has started. Also known as LIVE betting, bookmakers post multiple in-play betting options throughout most major sporting events.
Joint favorite: Two or more sides posted with the same betting odds on the same event.
Juice: Also known as vigorish, juice is set by bookmakers and is attached to spread and total betting options. If Minnesota -3.5 (-110) versus Green Bay +3.5 (-110) has $110K wagered on both sides, bookmakers earn $10K profit from the juice on the losing bets.
Kentucky Derby: First jewel in the Triple Crown of thoroughbred racing. Race day is the first Saturday in May at Churchill Downs in Louisville, Kentucky.
Larry O'Brien Trophy: Awarded annually to the champion of the NBA Finals.
Laying points: Betting on a favorite. A wager on Dallas, as a -2.5 point favorite over the LA Rams, is laying 2.5 points. The Cowboys need to win by at least points to cash a winning ticket.
Layoff: Used by bookmakers and players to reduce risk on a certain market. Parlay bettors may have an option to place a layoff wager on both sides of the last open bet on a ticket to set up a guaranteed profit.
Limit: Bookmakers set various high and low wagering limits that vary by sport and betting options. As part of a proper bankroll management system, players should set and follow personal betting limits.
Line: Betting odds posted by a bookmaker.
Linemaker: Same as a bookmaker, a person or group that sets daily betting lines and prices.
Listed pitchers: Appear with daily baseball betting odds. If a listed pitcher doesn’t start the game, bets are usually voided and the original stakes are returned.
Live betting: Also known as in-play wagering, live betting is offered once a sporting event begins. Spreads, moneylines and totals are adjusted and re-posted as a match plays out. Prop options, like next goalscorer and correct final score, are also available.
Lock: Term often used by tipsters to tempt bettors into buying handicapping advice. Death and taxes are the only true locks in life.
Longshot: A perceived inferior side that is also known as an underdog. Longshot prices are always displayed as positive prices. The New York Jets, with a +9.5 point spread, would be a longshot against the New England Patriots.
March Madness: NCAA college basketball National Championship tournament held annually over three weeks from mid-March to early April.
Masters Tournament: First of four major Grand Slam golf tournaments. Held annually in the middle of April at the Augusta National Golf Club in Georgia.
Middle: Cashing tickets on both sides of a betting option. Bettors have an opportunity to middle when a point spread moves up or down prior to a match.
MLB: Major League Baseball is the world’s top ranked baseball league and consists of teams that are based in the United States and Canada.
MLB Draft: Held every June, MLB teams select prospects from colleges, amateur baseball teams and high schools. The MLB draft is five rounds and most of the players selected will be assigned to minor league teams.
MLS: Major League Soccer is the top ranked soccer league in North America and consists of teams that are based in the United States and Canada.
Moneyline: A straight up bet, without any point spread, where bettors need to predict the outright winner. Favorites are posted with a negative (-185) odds while underdogs are listed with a positive (+165) price.
Multiple bets: Same as parlay, multiple bets are a single wager that consists of at least two sides on a single ticket. All sides must win (or push) to cash winning multiple bets.
· Double: Single parlay ticket with two sides.
· Treble: Single parlay ticket with three sides.
· Trixie: Three sides create three double bets and one treble bet.
· Patent: Three sides create three single bets, three double bets and one treble bet.
· Yankee: Four sides create one four-leg parlay, six double bets and four treble bets.
· Lucky 15: Four sides create four single bets, one four-leg parlay, six double bets and four treble bets.
· Lucky 31: Five sides create one five-leg parlay, five four-leg parlays, five single bets, ten double bets and ten treble bets.
MVP: Player honored as most valuable to their team during the regular season or playoffs. Tom Brady is a four-time Super Bowl MVP. Wagering on who will be named the Most Valuable Player is a popular futures betting option in professional sports.
Nap: Similar to a lock, a nap is a handicappers suggested best bet on a daily betting card.
NASCAR: National Association for Stock Car Auto Racing is the governing body of stock car racing.
NBA: National Basketball Association is the world’s top ranked basketball league and consists of teams that are based in the United States and Canada.
NBA Draft: Held every June, NBA teams select amateur players during a two round draft.
NCAA: Governing body for all USA college sports.
NFL: National Football League is the world’s top ranked gridiron football league and consists of teams that are based in the United States.
NFL Draft: A seven round event held every April where NFL teams select top college football prospects.
NHL: National Hockey League is the world’s top ranked hockey league and consists of teams that are based in the United States and Canada.
NHL Draft: Held every June, NHL teams select college players, plus pro European prospects, during a seven round draft.
No action: Betting options cancelled by a bookmaker are graded as no action. Original stakes are returned to bettors.
Novelty bets: Prop and special betting options that are wagers beyond standard moneyline, point spread and game total odds. Team and player propositions are the most common novelty bets.
Odds: Betting lines set by a bookmaker on a variety of events.
Odds formats: American (+100), Decimal (2.00) and Fractional (1/1) are the three main odds formats.
Oddsmaker: Same as a linemaker, a person or group that sets daily betting lines and prices.
Odds on favorite: One side that is viewed as far superior to the other and is priced with odds that offer very little value.
Odds shopping: Reviewing the lines at a variety of sportsbooks in order to find the best priced odds.
Off the board: Shortened to OTB, off the board games are displayed on betting boards but don’t have odds attached to them. An injury to a star player may cause bookmakers to pull odds off the board.
Outright betting: Predicting the overall winner of a tournament or playoff competition.
Over bet: Opposite of an Under bet on game total options. If the total on a Bengals versus Cardinals NFL match is set at 41.5 points, players who place over bets need the combined final score to be 42 points or more.
Over/Under: A number posted on how many runs/goals/points will be scored in a match. Bettors need to determine if the combined scores of both teams will go over or remain under the number.
Parlay: A single bet, also known as an accumulator or multiple, that consists of two or more sides. Each side must win to produce a winning ticket. A selection that ends as “push” is voided from a parlay ticket.
Parlay banker: Forming the base of a parlay wager, a banker is a favorite side to which other sides are added. New York (-130) would be the banker with Detroit (+110) and Chicago (+120) on a parlay ticket.
Payout: The amount a bettor collects on a winning wager. When a wager is placed, the possible payout on a betting receipt usually includes the original stake.
PGA Championship: The second major Grand Slam golf tournament of a PGA season. Held in late May at various courses across the United States.
Pick ’em: A betting option where the odds are exactly the same on both sides. Atlanta (-110) vs Miami (-110) is a pick ’em wager.
Point spread: Odds posted on a match that are designed to level the playing field. Favorites are listed with a negative (-6.5) point spread while the underdog is given a ‘head start” with positive (+6.5) odds.
Post time: Scheduled start time of a race. Horses are “at the post” once all of them are loaded into the starting gate.
Power rankings: A ranking system that uses a variety of criteria to grade teams, in a specific league, from the best to worst.
Preakness Stakes: Second jewel in the Triple Crown of thoroughbred racing. Race day is two weeks after the Kentucky Derby, on the third Saturday in May, at Pimlico Race Course in Baltimore, Maryland.
Price: Another term for betting odds and/or juice set by a bookmaker.
Proposition bet: Often shortened to prop bet, proposition bets are exotic or special wagers that are offered on most sporting events. NFL Super Bowl prop betting options number in the hundreds.
Proxy: A proxy is an individual, or a group of individuals, who place bets for other people. The term is most commonly associated with people who submit picks for non-Las Vegas residents that are involved in season-long sports pools like the Westgate Las Vegas SuperContest.
Public money: Amount wagered by the general public on any betting option.
Puck line: Point spread pricing in hockey. Prior to a match, the favorite is normally posted at -1.5 goals while the underdog receives +1.5 goals.
Push: Any wager where the final result is a tie. If a basketball spread is 11 points and the final score is 120-109 spread bets on both teams are graded as a push and original stakes are returned.
Quarter Bet: Any wager placed prior to or during any quarter of a sporting event. Prior to an NBA game, Boston may be a -1.5 point favorite to win the first quarter against Philadelphia who would +1.5 underdogs. LIVE betting odds will change often as the first 12 minutes of the match play out.
Recreational Bettor: A player that bets infrequently or on major sporting events only. Rec player bets are counted as public money. Opposite of a sharp or professional bettor.
Rotation Number: A number assigned by bookmakers to every betting option on the board. Bettors use the rotation number when placing a bet, rather than team names, at betting windows at land based sportsbooks.
ROY: Honors the top first year player in most professional sports leagues. Wagering on which player will be named the Rookie of the Year (ROY) is a popular futures betting option.
Run Line: Point spread pricing in baseball. Prior to a game the favorite is normally posted at -1.5 runs and the underdog odds are listed at +1.5 runs. When live betting, depending on the score of the match, runs lines increase and/or decrease as a game progresses.
Second half bet: Any wager that focuses on the outcome of the second half of any competition. Bettors can place wagers before the second half begins or make live bets once the match resumes.
Selke Trophy: Awarded to a forward (not a defenseman or goaltender) with the best defensive skills during the NHL regular season.
Sell points: Bettors can sell points by using alternate point spreads and game totals. In football, if a player moves a line from -6.5 to -7.5 they have sold one point. Juice becomes more favorable for the bettor with each point sold.
Sharp: A professional sports gambler who uses vast resources to determine their wagers. Sharps look at the big picture and base their bets on knowledge. Pro bettors always shop around for the best prices and will bet on favorites or underdogs when they receive proper value.
Special: Similar to prop and exotic wagers, special bets are added to a competition beyond the more common moneyline, game total and spread betting options. Hundreds of specials are offered during major events like the FIFA World Cup soccer tournament.
Spread betting: Taking or laying points when betting on a competition. Selecting Los Angeles at -7 point odds against New York (+7) is a spread bet. The Rams need to defeat the Giants by at least eight points to cash a winning ticket. Bettors lay the spread with favorites and take the spread with underdogs.
Sportsbook: A free standing shop, or in dedicated space at land based casinos, sportsbooks have become popular meeting spots for bettors and sports fans alike. Sportsbooks accept bets on US events, plus action from around the globe, and provide giant screens for bettors to watch the action play out.
Square: Another term for a novice or recreational player and the opposite of a sharp or professional bettor.
Stake: The amount of money a bettor risks when placing a bet. Original stakes are returned on all winning wagers and many bets that are graded as a push.
Staking method: Differs from bettor to bettor. Some players set maximum stake limits on each bet they place while others use a bankroll percentage as their stake.
Stanley Cup Trophy: Awarded annually to the top team in the NHL Stanley Cup playoffs.
Steam: Odds that change quickly usually due to a large amount of betting action by sharp bettors or syndicates.
Straight bet: A single wager on moneyline, spread or game total betting options.
Syndicate: A group of bettors that pool funds and use their combined knowledge to bet on events. Syndicates will often wager large amounts to move a line and then place an even larger bet on the new price they helped create.
Taking points: A bet placed on an underdog side. Bettors who wager on Washington, with a +1.5 run line, are taking points on a baseball bet. Tickets cash is the Nationals win outright or lose by one run.
Teaser odds: Any line moved up or down by a bookmaker to entice (tease) bettors. Players can tease odds on a single game by using alternate lines. They can also place a parlay bet from a teaser card issued by a sportsbook.
Teaser Card: A daily list of all games, from one specific sport, where the odds are higher or lower than the prices posted on the main betting board. Teaser card bets require selecting two or more sides.
Ted Lindsay Award: Most valuable NHL player award as voted on by active hockey players only.
Ticket: A receipt issued by a bookmaker to confirm a wager has been accepted.
Tip: Betting advice offered by tipsters and handicappers that suggest the most likely outcome of an event. Tips should never be bet on blindly but can be helpful when used with a proper pregame research plan.
Tipster: A person or group that offers betting advice. Some tipsters offer free sports wagering advice while others charge a fee for their tips.
Triple Crown: Three horse races, the Kentucky Derby, Preakness Stakes and Belmont Stakes, which form the thoroughbred Triple Crown racing series.
The Open Championship: Fourth and final major Grand Slam golf tournament. Held annually in late July at a golf course in the United Kingdom. Also commonly known as The Open or the British Open.
Three-way odds: Wagering options that have three sides and include ties as a betting option.
Two-way odds: Wagering options that have two sides and do not include ties as a betting option.
Under: Opposite of Over on game total betting. If the total on a Lakers vs. Clippers match is set at 238, players who place under bets need the combined final score to be 237 points or less.
Underdog: Perceived to be the inferior side, underdogs are posted with a positive number. If Washington is listed with (+280) odds, in a match against Dallas, the Redskins are the underdog and must win outright to cash a winning NFL moneyline ticket.
U.S. Open (Golf): Third of four major Grand Slam golf tournaments that is played in the late June at various golf courses in the United States.
U.S. Open (Tennis): Fourth and final women's and men's Grand Slam tennis tournaments that are played over two weeks in late August and early September at Flushing Meadows–Corona Park in Queens, New York.
Vezina Trophy: Awarded to the most valuable goaltender during the NHL regular season.
Vigorish: Another term for juice. Standard vigorish pricing is (-110) and bettors need to wager $110 to earn a $100 return.
Vince Lombardi Trophy: Awarded annually to the winner of the NFL Super Bowl.
Wager: Placing a bet on any event offered at a sportsbook, casino or racebook.
Westgate SuperContest: Established in 1988, the Westgate Las Vegas SuperContest is branded as the ultimate football handicapping challenge. Focused on the NFL regular season, there are three contests to choose from: the SuperContest, SuperContest Gold and SuperContest Reboot.
Wimbledon: Third of four women's and men's Grand Slam tennis tournaments that are played over two weeks in late June and/or early June. Wimbledon is played at the All England Lawn Tennis & Croquet Club in London.
Wise Guy: Handicappers, sharps and professional bettors with vast knowledge of the sports they bet on.