What is MLB (Major League Baseball)? What is different, Japanese professional baseball and MLB?
United States consists of Major League and Minor League. MLB consists of a total of 30 professional baseball teams of 14 the American league and 16 National League  -- having -- the bottom of each team -- 3A and -- the team of the minor leagues divided into 2A , A , and the rookie -- it is -- everybody -- it goes up upwards in an order from a rookie league.However, the probability which goes up from a rookie to MLB is the severe competition of grade 3% to 5%.
Each professional baseball team of the Major Leagues is called by the name + nickname of the city and state which place headquarters by the perfect headquarters (franchise) system, and does not put in the name of an owner company like [ of Japan ] by it.

National League was established in 1876, and, as for the history of MLB, establishment and eight professional baseball teams joined [eight professional baseball teams / affiliation and the 1901 American league].They are a total of 30 professional baseball teams of the present 14American league and the 16National league.
1920 Japan movement association formation is carried out, and Central League 6 professional baseball team and Pacific League 6 professional baseball team unite the history of Japanese professional baseball now, and they are 12 professional baseball teams.

It is 1908 that the U.S. pro team visited Japan for the first time on Japan-U.S. baseball.Sport shop called U.S. “reach” composed the team for the purpose of selling expansion, and held the university in Japan, etc. and 17 games.

Although a home run ball can be got in the stadium Japan professional baseball of the United States and Japan, even if a foul ball flies, you have to return it.On the other hand, that to which, as for MLB, the home run ball and foul ball has also flown can be got.The bat which has flown as well as it can be got.However, since the bat which has flown is a player's thing, I have it exchanged for another bat.