Pocket Monsters Red and Green were first released in Japan on February 27, 1996.
The games were developed by Game Freak for Nintendo's Game Boy. They introduced the central Pokémon formula: exploring, catching creatures, training them, battling, and trading with other players.
The Japanese releases were called Pocket Monsters Red and Green. International players later received Pokémon Red and Blue, because the Japanese Green version was not initially released overseas. This difference often causes confusion when people discuss the franchise's original pair of games.
The February 27 date became known as Pokémon Day, an annual celebration of the franchise. The 30th anniversary in 2026 marks three decades since those original Japanese releases began Pokémon's worldwide expansion.