Home run (baseball)

How it is scored and its effects

When a home run is scored, the batter and any baserunners touch all bases and each crossing of home plate counts as a run. The batter is credited with a hit and an at‑bat, which affects batting average, on‑base percentage and slugging; the play also produces runs batted in (RBIs) for the batter equal to the number of runners that score, including himself. Official scorers determine whether any defensive misplay constitutes an error; if an error occurs that allows additional bases, the scorer may alter how the advance is recorded.

Common types

• Over‑the‑fence: The ball is hit in fair territory and clears the outfield barrier—this is the archetypal home run.
• Inside‑the‑park: The ball remains in play and the batter runs all the bases and scores before play is stopped. These are rarer and often involve unusual bounces, deep outfields or defensive positioning. Official scoring requires that no error be charged to the defense for the batter's advance to be recorded as an inside‑the‑park home run; see an example discussion of the term inside‑the‑park.
• Ground‑rule and other rulings: Fan interference, ground rules unique to a stadium, or obstruction can affect whether a hit is ruled a home run; umpires and scorers apply specific rules in each case.

History and notable rule developments

The treatment of game‑ending hits evolved during baseball's early decades. In the past, a blow that sent the winning run home before the batter himself reached the plate was sometimes not recorded as a home run in the batter's statistics; such situations could deny a batter a credited homer even when the ball cleared the fence. Modern rules now award the batter the full home run and any associated RBIs in a game‑ending situation, commonly called a "walk‑off". Historical examples involving early stars such as Babe Ruth illustrate how scoring conventions have changed. For modern interpretations of play dynamics, see materials on defense and fielding.

Impact, examples and records

Home runs are a central offensive statistic and a major contributor to team scoring. They produce dramatic moments, especially when multiple runs score on a single swing. Several players have dominated home run leaderboards in different eras; long‑standing discussions of career and single‑season leaders often mention figures like Babe Ruth, Barry Bonds and Hank Aaron as historic benchmarks. Single‑game feats and milestone totals are frequently referenced in baseball histories and broadcasts.

Distinctions, scoring nuances and common terms

• "Solo", "two‑run" and "grand slam" describe whether the home run scored one, two or the maximum number of runs with the bases loaded.
• Scorers distinguish between earned and unearned runs for pitchers, and whether a baserunner's advance was due to an error affects the play's classification; see related guidance for official scorers and team defense.
• Because stadiums and boundary definitions differ, a hit that would be a home run in one park might be judged differently in another; consult stadium ground rules and umpire rulings for specifics.

For further reading on rules, scoring and historical examples, consult official rulebooks and authoritative histories of the game. Additional resources and modern coverage of the subject are available via sport governing bodies and analytical outlets: basic rules, statistical treatments, historical leaderboards, defensive analysis, fielding strategy, inside‑the‑park cases and biographies.