A golf handicap is a number that is used to make the competition between players of differing skill levels more even. The number is calculated using a complicated formula that takes into account the golfer's adjusted gross scores and the difficulty of the course. The lower the number, the better the golfer. A "scratch" golfer is one with a handicap of 0 or better.
When two golfers with different handicaps play together, this number is used to even the playing field. At it's most basic, if a person with a handicap of 2 plays against someone with one of 10, the first person cuts two strokes off his or her score final score, while the second person cuts 10 strokes off his or her final score. The scores are then compared to see who won.
For a golf handicap to be official, it typically has to be obtained through an organization like the United States Golf Association (USGA). The formula for figuring it out takes into account the difficulty of the course on which a round was played to give a more accurate representation of a golfer's skill level. To do this, the USGA assigns what is called a slope rating to each set of tees on each course.
The slope rating is also used to determine the number of strokes a golfer gets at a particular course. A person's golf handicap and the slope rating are input into a formula that determines the handicap the person will use for that course. This number can differ from the player's handicap depending on the difficulty of the course. Since not all courses have the same level of difficulty, this makes player handicaps more relevant to the course being played.
Handicaps can be used to level the competition between two players or in a larger tournament. In a tournament setting, each player's number is applied to his or her gross score, and the net score is used to determine the winner.