The Basics

Baseball is played between two teams of nine players on a field arranged around four bases set at the corners of a square ninety feet apart. The team at bat attempts to score runs by hitting a pitched ball and advancing around the bases. The team in the field attempts to prevent this by getting three outs per half-inning, after which the teams switch roles.

A standard game lasts nine innings. Each inning consists of two halves: the visiting team bats first, then the home team. If the score is tied after nine innings, extra innings are played until one team leads at the end of a complete inning. Games can, in theory, go on indefinitely.

There is no clock. Baseball is the only major American team sport that is not governed by time. An out ends a half-inning; a run ends a game. This is not a small thing. It means that no lead is ever truly safe, and no deficit is ever mathematically final until the last out is recorded.

The Field

The playing field is divided into the infield and the outfield. The infield contains the four bases: first, second, and third base, and home plate, where the batter stands. The pitcher's mound sits at the centre of the infield diamond, sixty feet and six inches from home plate — a distance arrived at by accident in 1893 when the rules committee misread their own handwriting.

The outfield extends beyond the infield to the outfield wall, whose distance from home plate varies from stadium to stadium. This is unique among major sports: the dimensions of a baseball field are not standardised. Some outfield walls are close; some are far. Some are padded. One, at Fenway Park in Boston, is covered in tin and is thirty-seven feet tall. It is called the Green Monster.

Pitching

The pitcher is the most important position in baseball. From sixty feet and six inches away, a major league pitcher throws a ball weighing five and an eighth ounces at speeds that regularly exceed ninety-five miles per hour. The ball reaches the batter in roughly four-tenths of a second. The batter has about two-tenths of a second to decide whether to swing.

Pitchers do not simply throw the ball fast. They throw it with spin, with movement, and with deception. A curveball breaks downward. A slider breaks sideways. A changeup looks like a fastball but arrives fifteen miles per hour slower, disrupting the batter's timing. A well-executed changeup is, in some ways, more impressive than a fastball that exceeds a hundred miles per hour.

Starting pitchers are expected to pitch deep into games. Relief pitchers are specialists brought in to handle specific situations — or specific batters. The closer pitches the final inning when the lead must be protected. The entire structure of a pitching staff is a complex, evolving system of management and deployment that managers spend entire careers trying to master.

The Batting Order and Lineup

Each team sends nine batters to the plate in a fixed order, called the batting order, which does not change during the game except when a player is substituted. The leadoff hitter is typically the fastest and best at reaching base. The cleanup hitter, batting fourth, is typically the team's best power hitter, expected to drive in runners who have reached base ahead of him.

A batter is awarded a base on balls, or walk, if the pitcher throws four pitches out of the strike zone without the batter swinging. A batter who accumulates three strikes — whether by swinging and missing, or by taking a pitch in the strike zone — is out on a strikeout. These two facts drive much of baseball's strategic tension.

The Statistics

Baseball is the most statistically documented sport in human history. Every action on the field has been counted, categorised, and analysed since the 1870s. Batting average, earned run average, on-base percentage, slugging percentage, wins above replacement — the vocabulary of baseball statistics has grown into its own language, one that fans and front offices speak fluently.

The rise of sabermetrics — the empirical analysis of baseball statistics — transformed the sport in the early 2000s. The book Moneyball, by Michael Lewis, described how the Oakland Athletics used statistical analysis to compete with teams that had far larger payrolls. The ideas it popularised have since been adopted by every team in the league, and have spread to nearly every other sport.

Culture and History

Baseball was codified in New York in the 1840s and spread rapidly across the United States during and after the Civil War. By the end of the nineteenth century it was the national pastime, a phrase that stuck even as the sport's cultural dominance eventually gave way to American football.

The Negro Leagues, founded in 1920, gave Black players a place to compete when they were excluded from the major leagues by a policy of segregation that lasted until Jackie Robinson broke the colour barrier in 1947. The Negro Leagues produced some of the greatest players in the history of the sport, most of whom never had the chance to play in the major leagues. In 2020, Major League Baseball officially recognised the Negro Leagues as major leagues, incorporating their statistics into the historical record.