Significance
A hole in one is usually accomplished on a par 3. A par 3 is so called because an accomplished golfer should be able to take one shot to reach the green and two putts to get the ball into the hole. Getting a hole in one on a par 3 means the player shot two under par, or achieved what is known in golf as an eagle, though most do not use that term on a hole in one.
Types
While the most traditional hole in one is on a par 3, there are other types of holes where they can be achieved. To a lesser extent, a hole in one can take place on a par 4. In fact, a few holes in one have even been verified on Par 5 holes.
Potential
According to Golf Digest, the odds of a Professional Golf Association player hitting a hole in one is 1 in 3,756. The odds of the amateur player making a hole in one has been put at 1 in 12,000 to 1 in 40,000 on a par 3, depending on the source. The odds of acing a par 4 are at least 1 in a million. The odds for an ace on a par 5 are so astronomically high that there are no odds calculated.
For more information, see additional resources below.
Considerations
The way to increase your odds of hitting a hole in one is to play as many rounds as possible. Some golf courses are made up exclusively of par-3 holes. This increases your chances of a hole in one. A typical golf course usually has no more than five par-3 holes.
For more information on par-3 courses, see additional resources below.
Benefits
The biggest benefit that comes from hitting a hole in one is the bragging rights that comes with it. A hole in one is a special occasion and will be celebrated for years. Some even hold anniversary celebrations for hitting a hole in one. Of course, golfers in a competitive foursome are also likely to gain an advantage on their opponents--at least for that one hole.
Warning
Tradition dictates, at least in some areas and among some foursomes, that a player who hits a hole in one must buy everyone in the clubhouse a round of drinks. This could be a very expensive proposition. In some cases, it encourages some golfers to keep a hole in one quiet until well after the event has passed.
For more information on hole-in-one traditions, see additional resources below.