Video games
When Pokémon was first released in Japan in 1996, it was named Pocket Monsters. Someone else had trademarked this name in North America, so Nintendo had to change the game title. Many Japanese players had already shortened the game name to 'Pockemon' and the name stuck.
The initial games introduced the concept of becoming a Pokémon Trainer and catching all 151 original Pokémon.
The Pokémon games are classified as role-playing games because they have elements similar to other RPGs, such as a top-down tile-based point-of-view, item management, and a turn-based battle system with familiar elements like hit-points and status effects. They do not focus on plot and character development in the manner of Final Fantasy and many other RPGs. Instead, Pokémon games focus on the collection and training of creatures which are sent into battle against opponents (either AI-controlled or other fellow humans). Depending on the game in the series, there may be 151 or 251 available Pokémon, and in Pokémon Ruby and Sapphire, there is a set of 202 with 67 from previous games, though there are 387 in total. A player's Pokémon can be traded with other players via the Game Boy Link Cable; this forms an integral part of the game as some Pokémon can only be collected by trading with another version.
A Pokémon game begins in the hero(ine)'s hometown, where by chance the renowned Professor of the game's region (Kanto, Johto, or Hoenn) lives and does his research on Pokémon. It is from him that one can receive his or her starting Pokémon to train on your journey. Along the way one will encounter a rival who has also received a starting Pokémon from the professor, and the rival's Pokémon will be strong against his or her Pokémon based on type (Grass is weak against Fire, Fire is weak against Water, Water is weak against Grass). Despite this, one's goal is to collect the eight badges from the eight Gym Leaders scattered throughout the land. The badges allow one to challenge the Elite Four and the champion trainer of the land. To do this, one must capture and train a team of Pokémon that will ensure his or her victory, and also complete in side quests such as thwarting the diabolical plans of the criminal organization in the area. After beating the Elite Four and the champion, one is allowed to continue training and collect Pokémon, especially the hard-to-catch Legendary Pokémon, which are powerful and one-of-a-kind.
To capture wild Pokémon, one must carry Pokéballs with him or her. When one encounters a wild Pokémon that he or she wishes to capture, he or she must first weaken it with a Pokémon in his or her collection and then toss a Pokéball at it to catch it. He or she might or might not be successful, but with each Pokéball he or she tosses, he or she has another chance.
A whole subculture exists which is devoted to the study of Pokémon battling and strategy. Usually research centers around Internet bulletin boards such as the GameFAQs forums,
Azure Heights and The Pokemasters. The Pokémon games have also inspired the Poké Battles form of fiction.
Different aspects of battle mechanics include:
The Pokémon games are (in system order, then in release order):
Gameboy (monochrome) era
The first games star Satoshi (Ash Ketchum) as the main character and Shigeru (Gary Oak) as his rival. Nintendo apparently didn't want to favor any one real-world name over another. Therefore, in the U.S. version, they are usually not referred to as such; instead, their default names are "Red" or "Blue" ("Red" or "Green" in the Japanese versions), which "Ash" and "Jack" and "Gary" and "John" as other default names. A third character (known as "Blue" in Japan), although not playable in these games, is represented as a girl in a short, black dress. She wears white gloves and has long, brown hair with a small ponytail. Although she never appeared in the anime series, she has appeared in one of the mangas as well as on Japanese Pokémon products. In the Japanese Pokémon Crystal, she becomes a radio host.

- Red and Green were initially released in Japan on February 27, 1996.
- Blue was released in Japan on October 27, 1996. It featured improved graphics and sounds.
- North America would finally get its first releases of Pokémon, Blue and Red, on September 30, 1998. The North American versions were actually the Japanese Green and Red with the new changes and graphics that the Japanese Blue had.
- On September 12, 1998, Pokémon Yellow was released in Japan. It was initially known as "Pocket Monsters Pikachu," as it was based off of the (by this time very popular) animated cartoon series. In this game, the player's character would start with Pikachu instead of getting to choose.
- On October 25, 1999, North America got its version of Pokémon Yellow, named "Pokémon Yellow Version: Special Pikachu Edition." It would remain much the same as the Japanese version.
Gameboy Color era
The plot of the next round of games takes place three years after the first series. Again, the characters' only official names are colors, but now there is no pre-set name for the rival. These games also make Ash's official Gameboy name "Red", and Gary's "Blue", a fact that was carried over to Pokémon Stadium 2. This series also introduces the first playable female character, Crystal.

- On November 21, 1999, Pokémon Gold and Silver were released in Japan. These two games introduced a total of one hundred brand new Pokémon and the new region of Johto, and had limited compatibility with the previous versions.
- North America got its versions of Gold and Silver on October 11, 2000.
- Pokémon Crystal, the Ultimate version of Gold and Silver, was released in Japan on December 14, 2000. Many fans feel this version is what Gold and Silver should have been in the first place. It was the first version to allow players to choose if they wanted to be a male or female character, and the Japanese version of Crystal included (in a first for a handheld system) the ability to go head to head online over Japanese cell phone networks.
- On July 21, 2001, North America received Pokémon Crystal. However, the North American version did not include the online component.