Triple
The rarest hit that is not a home run, and the only one that needs a fast man and a strange ballpark together.
What it actually is. A triple is a hit on which the batter reaches third base. It requires the ball to get a long way from a fielder and the hitter to be fast enough to run 270 feet before the relay arrives, which is why it is the least common hit in the game.
What somebody who knows the game gets out of it. The triple is the best surviving evidence that ballparks are not interchangeable. It needs a deep gap, a big outfield or an odd wall angle, so its rate is as much a fact about the stadium as about the hitter. Historically its decline tracks the standardization of outfields: parks with 460 foot center fields produced triples, symmetrical modern parks with warning tracks do not. A hitter leading the league in triples is usually telling you three things at once, that he is fast, that he drives the ball into gaps, and that he plays half his games somewhere unusual.
The numbers worth knowing. Ten triples is a lot now. Twenty is a season people remember. In 1912 the league hit roughly twice as many per game as it does today, and the leaders were regularly in the twenties.
What people get wrong about it. A triple is not a double the runner stretched. It is scored as a triple only if he was not going to be out with ordinary fielding; if the defense gave it to him with a throw to the wrong place, the scorer can rule it a double plus an error or simply a double and an advance. Scorers vary on this more than they should.
At Little League and travel ball. On youth fields with no fence or a very deep one, triples are common and mean much less. A ball past a 10U outfielder rolls until somebody gets to it, so a triple frequently reflects the defense rather than the hitter's speed at all.
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