Explanation:
Minor League Baseball (MiLB) is a hierarchy of professional baseball leagues in the Americas that compete at levels below Major League Baseball (MLB) and help prepare players to join major league teams. All of the minor leagues are operated as independent businesses. Most are members of the umbrella organization formally known as National Association of Professional Baseball Leagues (NAPBL), which operates under the Commissioner of Baseball within the scope of organized baseball. Several leagues, known as independent baseball leagues, have no official links to Major League Baseball.
Except for the Mexican League, teams in the organized minor leagues are generally independently owned and operated but are directly affiliated with one major league team through a standardized Player Development Contract (PDC). These leagues also go by the nicknames the "farm system", "farm clubs", or "farm teams" because of a joke passed around by major league players in the 1930s when St. Louis Cardinals general manager Branch Rickey formalized the system, and teams in small towns were "growing players down on the farm like corn".
Major League Baseball and Minor League Baseball teams may enter into a PDC for a two- or four-year term. At the expiration of a PDC term, teams may renew their affiliation, or sign new PDCs with different clubs, though many relationships are renewed and endure for extended time periods. For example, the Omaha Storm Chasers (formerly the Omaha Royals and Omaha Golden Spikes) have been the Triple-A affiliate of the Kansas City Royals since the Royals joined the American League in 1969, but the Columbus Clippers changed affiliations, after being associated with the New York Yankees from 1979, to the Washington Nationals in 2007, and have been affiliated with the Cleveland Indians since 2009.
A few minor league teams are directly owned by their major league parent club, such as the Springfield Cardinals, owned by the St. Louis Cardinals, and all of the Atlanta Braves' affiliates except the Florida Fire Frogs. Minor League teams that are owned directly by the major league club do not have PDCs with the parent club and are typically not part of the reaffiliation shuffles that occur after each even-numbered season.
As of 2018, there were 14 MLB-affiliated minor leagues with a total of 160 revenue-generating teams, located in large, medium, and small cities and suburbs across the United States and Canada, and there are three MLB-affiliated rookie leagues with a total of 80 teams, located in Arizona, Florida, and the Dominican Republic, though these teams do not generate revenue.[1]
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