Pokémon Red and Blue version were the first games of Pokémon! They are playable on the GameBoy. Here are the only Kanto Pokemon (151) and there is no access to the island Sevii. Below is further explanation.
History from Pokémon Blue version
the 2 real games were normal Red and Green. There was thus blue yet. First it was Red and Green available on the Japanese market. Later forests they are the first Pokemon games sell in the United States of America. they wanted to sell but not Red Green. So she made Blue. why not Green:
- They thought that the color blue more than green were selling.
- They found the Graphichs not so good
- a few other details.
Eventually they sold than Red and Blue. So Green was not in the U.S.A. In Europe, therefore, Red and Blue version. Later they have on the Japanese market also sold Blue. that was a bit of the history of Blue version.