Caddie
A caddie is the person who carries your bag and advises you during the round.
The caddie is far more than a carrier. They know the course, give distances, read the putt line with you and recommend clubs. In the professional game they are a fixed part of the team; in amateur golf you meet them above all at some traditional facilities or at tournaments with a compulsory caddie. In terms of the rules: you are responsible for the actions of your caddie. If they breach a rule, you take the penalty. Conversely, they may do certain things for you, such as rake the bunker or tend the flag.
An example from practice: you are standing on an unfamiliar course 145 meters from the flag, the wind comes from the left. Your caddie tells you that the green falls away behind the flag and that the safe number is 140 meters to the middle of the green. You take the iron they recommend instead of chasing the flag. Exactly this kind of support makes the difference. Distances and hole notes they often keep in a yardage book.
Typical misconception: many believe a golfer may take advice from anyone. In fact only your caddie or a partner may advise you, not just any fellow player or spectator. Another mistake is the idea that the caddie decides. They advise; the shot is played by you — and you answer for it too. Anyone playing without a caddie takes on their tasks themselves and gladly resorts to a golf trolley instead.
FAQ
Who is even allowed to advise me during a round?
Only your caddie or your partner in a foursome — nobody else. Advice from fellow players, spectators or the group behind you breaches the rules and can cost penalty strokes. Questions about general information such as distances on a board are allowed, however, because that is not advice.
What may a caddie do for me on the course?
More than most think: they may rake the bunker, tend the flag, mark your ball and carry your bag or put it on the golf trolley. They may also read putting lines with you and recommend clubs. If they act against the rules, however, you take the penalty — you are responsible for your caddie.
How do I replace a caddie when I play on my own?
With preparation and technology. A rangefinder provides the distances, notes or a yardage book replace the course knowledge, and honest self-assessment replaces the club recommendation. What matters is taking on the role consciously: pause briefly before every shot and go through the questions a caddie would ask you.