If you are watching a professional golf tournament live or on television, you occasionally will see an asterisk on the leaderboard next to a player's name. The PGA Tour uses the asterisk to indicate a player's starting position. Non-PGA tournaments might or might not use the asterisk.
As asterisk next to a player's last name on a golf leaderboard means the player began play on the back nine that day. With a quick scan of the leaderboard, you are able to note which players teed off on the front nine versus those who started on the back nine.
Knowing whether a player began play on the front nine versus the back nine helps you put his score in context. For example, if a player who started on the back nine finishes the 18th hole with a score of even par, he still has nine more holes to try to get under par.
Groups of PGA Tour golfers occasionally begin play on the back nine if, for some reason, the entire field needs to complete play that day in less time. If groups had to begin play one by one on the first hole, it would take longer for the entire field to complete the round. By starting half the group on the 10th hole, the field finishes in roughly half the time. Depending on the event, half the group might begin play on the back nine because an earlier round was suspended by inclement weather. Similarly, if the weather forecast indicates an approaching storm, half the field may start on the back nine to beat the storm.
In some professional tournaments, such as a U.S. Open where the field is especially large, half the players begin play on the back nine during the first and second rounds of play. By the final two rounds, the initial field has been cut in half, making it suitable to start everyone on the front nine.