Homerun

In baseball, a home run (abbreviated HR, also "homer", "dinger", "dong", "bomb", "blast", "goner" , "shot", or "four-bagger") is scored when the ball is hit in such a way that the batter is able to circle the bases and reach home safely in one play without any errors being committed by the defensive team in the process. In modern baseball, the feat is typically achieved by hitting the ball over the outfield fence between the foul poles (or making contact with either foul pole) without first touching the ground, resulting in an automatic home run. There is also the "inside-the-park" home run, increasingly rare in modern baseball, where the batter reaches home safely while the baseball is in play on the field. When a home run is scored, the batter is also credited with a hit and a run scored, and an RBI for each runner that scores, including himself. Likewise, the pitcher is recorded as having given up a hit, and a run for each runner that scores including the batter.

Home runs are among the most popular aspects of baseball and, as a result, prolific home run hitters are usually the most popular among fans and consequently the highest paid by teams—hence the old saying, variously attributed to slugger Ralph Kiner, or to a teammate talking about Kiner, "Home run hitters drive Cadillacs, and singles hitters drive Fords."

In modern times a home run is most often scored when the ball is hit over the outfield wall between the foul poles (in fair territory) before it touches the ground (in flight), and without being caught or deflected back onto the field by a fielder. A batted ball is also a home run if it touches either foul pole or its attached screen before touching the ground, as the foul poles are by definition in fair territory. Furthermore, many major-league ballparks have ground rules stating that a batted ball striking specific architectural features while in flight is a home run due to their location beyond the outfield wall.

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Wikipedia