Editing Baseball rules (section)

==History==
Unlike many other sports, the Official Baseball Rules have remained mainly static during the modern era of the game. Many baseball players, fans and administrators view the rules and traditions of professional baseball as time-tested and nearly sacrosanct.

This was not the case during baseball's early days, particularly in the late 19th century, when rules were changed significantly and often yearly. The modern game began to take shape in the late 1880s, with additional significant rule changes made during the rest of that century.

===Early era (pre-1901)===
{{See also|Origins of baseball}}
Many of the modern rules of baseball originated with the so-called [[Knickerbocker Rules|"New York game"]] played by amateur urban clubs of the 1840s and 1850s. These rules were first published in 1848 by [[Alexander Cartwright]], often credited as "the father of baseball", though they were actually written by [[William R. Wheaton]] and [[William H. Tucker (baseball)|William H. Tucker]], of the [[Knickerbocker Base Ball Club of New York|New York Knickerbockers]] club.<ref>{{cite news |first=John |last=Thorn |url=https://www.nytimes.com/2011/03/13/sports/baseball/13thorn.html |title=Debate Over Baseball's Origins Spills Into Another Century |work=[[The New York Times]] |date=March 13, 2011}}</ref>

In 1857, under the [[National Association of Base Ball Players]] (NABBP) Rules which governed until 1870, the 9-[[inning]] format was adopted, replacing the previous rule that the first team to score 21 runs won. The next year, called strikes were recognized, and a batter was out if a ball, fair or foul, was caught on the fly or after one bounce. Called balls and the walk were introduced in 1863. In 1867, the batter had the right to call for a high or low pitch, to be determined by the umpire.

The [[National League (baseball)|National League]] formed in 1876. Its rules changed almost yearly for the next quarter century. In 1880, a batter was out if the catcher caught the third strike; otherwise, the batter got four strikes. Before 1883, pitchers were required to deliver pitches with their hand below their hips; in that year, the rule was changed to allow shoulder-high deliveries. Until 1887, batters could call for either a high or low pitch, and the strike zone was either above or below the waist. In 1885, the rules changed, to allow bats to be flat on one side; beginning in 1893, they had to be round. In 1887, the rules changed so that batters could no longer call for a pitch; and the strike zone was defined as from the shoulders to the knees. During this period, the pitcher's mound was much closer to home plate, foul balls were not counted as strikes, batters got four strikes, and the number of "called balls" resulting in a walk—which initially included strikes and foul balls- went from 9 to 8 to 7 to 6 to 5 and, in 1889, to 4. In that same year, the number of strikes went from 4 to 3. In 1887, a rule was adopted for that year counting only walks as hits, which played havoc with statistics. In 1892, the 154 game schedule was adopted. In 1893, the pitching position was changed from behind a line 50 feet from home plate to contact with a rubber slab 60.5 feet away. In 1894, foul bunts were made strikes, and the [[infield fly rule]] was adopted with one out. In 1895, foul tips were made strikes, but not foul balls. In 1898, the first modern balk rule was adopted, as well as the rule for recognizing stolen bases. In 1901, the infield fly rule was extended to apply when there were no outs.

===Modern era (1901-present)===
Due to the frequent and often radical rule changes during this early period, the "modern era" is generally considered to have begun in 1901, when the [[American League]] was also formed.

Some significant rule changes continued in the first quarter of the 20th century, but were much less frequent. In 1903, the American League adopted the foul strike rule. In 1907, the sacrifice fly rule was adopted. In 1910, cork centers were added to balls. In 1925, the minimum distance for a home run was made 250 feet. Until 1929 (AL) and 1931 (NL), a ball that bounced over the outfield fence in fair territory was a home run, not a ground rule double.

After that, the rules remained virtually static for decades. Most top-level international leagues were formed during this period, including the [[Japanese Baseball League]] (1936) and its modern-day successor [[Nippon Professional Baseball]] (1950). Already-existing leagues in the Western Hemisphere were integrated into MLB's [[Minor League Baseball|minor leagues]] and thus subject to the OBR, namely the [[Cuban League]] (1947) and the [[Mexican League]] (1955).

In 1961, the 162-game schedule was adopted by MLB. In 1969, the pitcher's mound dropped five inches and the strike zone was reduced from the armpits to the top of the knees. In 1973, the American League adopted the [[designated hitter]] rule. This was probably the most controversial rule change in baseball's history and is still subject to lively debate. It was not adopted by the National League until 2022. Also controversial when adopted was the later introduction of [[interleague play]]. On the other hand, rule changes banning the use of steroids and other performance-enhancing substances have had widespread support as protecting the integrity of the game. 

The most recent significant rule changes to the OBR occurred in 2023, when [[Commissioner of Baseball|MLB Commissioner]] [[Rob Manfred]] introduced rules adding a [[pitch clock]], extra-inning base runners, and restricting [[infield shift]]s. These rules have been gradually adopted in North America (and in WBSC competition), but generally do not exist elsewhere in the world.