The purpose of the USGA Handicap System is to make the game of golf more enjoyable by enabling players of differing abilities to compete on an equitable basis. A Handicap Index compares a player's scoring ability to the scoring ability of a scratch golfer on a course of standard difficulty. Having a handicap index allows golfers to participate in more events (those that require a handicap index), have a measureable means of tracking improvement, and allows score adjustments to even the playing field when playing with golfers of different skill levels.
Another option is to post your scores to your LPGA Amateur Golf Association handicap profile using the new LPGA Amateur Golf Association app for iPhone or android phones. Post immediately after your round and it will be synced with your online account. To get the app go to your App Store or Google Play Store on your mobile device and search for LPGA Amateur Golf Association. Simply download the free app and sign in using your login and password.
Whether you are a newer golfer or someone who has played the game for years, if you don't have a handicap, consider establishing one. You will never find a better tool for measuring your progress and you might just be surprised at how much you enjoy watching that number drop.
USGA's Handicap FAQ