A number that represents your potential playing ability, so golfers of different skill levels can compete fairly. Under the World Handicap System, your Handicap Index is calculated from the best 8 of your last 20 rounds (adjusted for course difficulty). A 15-handicap is expected to shoot roughly 15 over par on a good day — so in a net competition against a scratch golfer, they'd receive 15 strokes. Lower is better; the point isn't your average score, it's your demonstrated potential.