Baseball is played at a number of levels, by amateur and professionals, and by the young and the old. Youth programs use modified versions of adult and professional baseball rules, which may include a smaller field, easier pitching (from a coach, a tee, or a machine), less contact, base running restrictions, limitations on innings a pitcher can throw, liberal balk rules, and run limitations, among others. Since rules vary from location-to-location and among the organizations, coverage of the nuances in those rules is beyond this article.
Following is a list of organized leagues:
- Youth Leagues
- Little League, a youth program, headquartered in Williamsport, Pennsylvania (USA).
- Dizzy Dean Baseball a youth program in the USA.
- American Legion Baseball, a youth program, headquartered in Indianapolis, IN.
- USSSA Baseball a youth and adult program, headquartered in Kansas City, Missouri (USA).
- Ripken Baseball, a youth program, headquartered in Baltimore, Maryland (USA).
- Babe Ruth League, a youth program, headquarted in Trenton, New Jersey (USA).
- High School
- In the USA, the National Federation of State High School Associations (NFHS) and each state association governs the play of baseball at the high school level.
- Collegiate Level
- List of Collegiate Summer Baseball Leagues
- NCAA, including NCAA Division I and the College World Series, are collegiate level baseball programs played in the USA.
- National Club Baseball Association (NCBA)
- International Competition
- Many international baseball events are coordinated by the International Baseball Federation, including The World Cup and The World Baseball Classic.
- As an Olympic sport, see earlier section on the status of baseball in the Olympic games, and the article "Baseball at the Summer Olympics."
- Semi-professional baseball
- Professional baseball
- Major League Baseball (MLB) in the United States;
- Minor League baseball in the United States;
- Negro League baseball, defunct since 1958, in the United States.
- All-American Girls Professional Baseball League
- Mexican Baseball
- Japanese Baseball
- Taiwan professional baseball
- Korean Baseball Organization (KBO)
- Australian Baseball
There are also smaller professional leagues in China, Italy, Germany, the Netherlands, and many others.