HR is an abbreviation for home run. A home run is scored when a batter hits a fair ball and scores on the play without being taken out or benefiting from an error. A hitter smashes the ball in the air over the outfield fence in fair territory practically every time he hits a home run.
The term "home run" came about because early baseball games were played under lights at night in cities, and it was necessary for players to have something to show for their efforts. So, they invented the home run, which you could see from far away, thus making them more exciting to watch than anything else that had ever been seen before.
Today, people use the word "home run" to describe any shot that goes out of the stadium and becomes a major part of the outcome of a game. For example, if a shooter hits a bullet that ends up in the audience, that's called a "home run". It means that the bullet went very, very far.
The phrase "out of this world" comes from baseball. In the early days of the sport, there were no statistics kept, so coaches would give players tips on how to improve their games by telling them what other players were doing. For example, if the pitcher liked someone else's batting style, he might say, "He's going back to school to get out of this world".
The number of home runs an individual player hits during a season is called that player's total.
In baseball, a home run is different from a normal hit by pitch because it travels farther. While a normal hit by pitch can happen only if the batter fails to swing at a thrown ball, a home run can be either a swinging or non-swinging event. A home run can also be scored even if the runner on first doesn't try to advance himself since runners are automatically awarded bases on balls until they attempt to advance. However, if the catcher deliberately throws at the batter to get him out, then this would be called a foul ball and not count as a home run for batting practice purposes.
The term "home run" was originally used to describe any shot that left the park but today is usually defined as such unless some part of the stadium stands or buildings are damaged by damage, in which case the ball may be returned to play if it is in the center field area. If the ball goes over the fence but not far enough to clear the stands, it is considered to be a double.
A home run can be either a ground rule double or a line drive, but not a fly ball. A ground rule double is legal as long as the ball comes to rest within the park boundaries. A line drive that bounces beyond the park boundaries is considered an out.
The term "home run" was originally used by fans in the stands to describe a ball hit over the fence that would have been a double before the fences were built up in front of some stadiums. But since those fences are now part of the stadium structure, it is no longer possible to hit any ball with the intent of bringing it back over the fence for a home run.
However, because these balls are still classified as fair balls, a player can try to score on them as if they were normal baseballs. If he gets credit for a home run, then he has increased his total number of bases safely stored away while reducing that of his opponent by one. The more common use of the term today refers to a ball hit over the fence that is not caught or stopped before reaching the wall.
In that case, the hitter receives all four bases, and any runners on base also score. A home run can't be returned to the field; if it isn't caught, it will drop in front of the stands where fans can reach it.
The term "home run" was originally used for baseball hits that traveled far enough to qualify as outs away from the park. The first recorded home run in America occurred on April 17, 1856, when John Montgomery, who played first base for the New York Mutuals, hit one against the Boston Red Caps that landed past second base but was caught by a spectator running along the track at Recreation Park. The fan ran with the ball and eventually threw it back to the fielder who had given up on catching it. The rule that bats and balls have to be made of wood was created to prevent players from killing each other with well-hit balls. Although aluminum and composite bats are now allowed in men's professional baseball, they're still banned in women's softball.
In 1895, the American Association adopted a new rule allowing home runs after several members of the Kansas City Royals participated in a promotional game called the Home Run Derby. The winner would receive $10,000 ($220,000 in 2017 dollars).