Pokémon

Pokémon is a video game series, anime, manga, and movie series that surrounds creatures called Pokémon and people who catch and raise them, known as trainers. Many things in the Pokémon world have been created in the name of Pokémon, such as the Poké Ball (a sperical capsule used for catching Pokémon), PokéCenter (a clinic for Pokémon), and Poké Mart (a store for items relating to Pokémon).

Core games
The gameplay of Pokémon, on the surface, is very easy to understand. The player is a kind of person who raises Pokémon and uses them in battle known as a trainer. Trainers can compete against other trainers to see which one is better than the other by pitting their Pokémon against each other. There are some trainers in the Pokémon world who act as bosses in the Pokémon games named Gym Leaders. These Gym Leaders, upon defeat by the player, will grant them a Gym Badge. Most of the time, a Gym Badge will be necessary to progress in the games to prevent weak players from going into areas they weren't ready for or can't go into due to the story. In generation seven only (excluding the Let's Go! games), the Gym Leaders function was absent and had been replaced by an alternative known as Island Kahunas.

The Pokémon Games
The Pokémon games are split into eight "eras" unofficially called generations (shortened to "gen") by fans. Somewhat like with generations of humans, the games in one generation would have their differences from a game in another generation, like the Pokémon count or included features.

A "core game" is any Pokémon game that follows the initial gameplay formula that the franchise introduced. Any games that cannot be considered a core game is called a side game.

Gen I
Pokémon...


 * Blue
 * Green
 * Red
 * Yellow

The Pokémon count is at 151. All are new in Gen I.

Gen II
Pokémon...


 * Crystal
 * Gold
 * Silver

The Pokemon count is at 251, with exactly 100 more added in Gen II.

Fun Fact: The move count is also at 251 now.

Gen III
Pokémon...


 * Channel


 * Colosseum (moar liek Kalosseum)


 * Dash


 * Emerald


 * FireRed


 * LeafGreen


 * Mystery Dungeon ... Rescue Team
 * Blue
 * Red


 * Pinball: Ruby & Sapphire


 * Ranger
 * Ruby
 * Sapphire
 * Trozei!
 * XD: Gale of Darkness

The Pokemin count has been bumped up to 386 now with 135 being introduced.

Fun Fact: This is the first generation to introduce non-core games. It's also the first to redo a previous generation.

Gen IV
Pokémon...


 * Battle Revolution


 * Diamond


 * Pearl


 * Platinum

Not starting with "Pokémon"


 * My Pokémon Ranch

The Pokeyman count is increased to 493 as 107 are new to the series.

Fun Fact: IV sounds like ivy. ...Professor.

Gen V
Pokémon...


 * Black (2)
 * White (2)

The Parkimihn count is raised to 649 now that the games have 156 newcomers.

Fun Fact: This is the first generation whose map is based on some area outside of Japan, New York. About damn time. It's also the one to have the least non-sequel installations thus far.

Gen VI
Pokémon...


 * Alpha Sapphire
 * Omega Ruby
 * X
 * Y

The Pookamen count is now at 721, jumping up by 72. This is the first generation in which the count of new Pokémon added to the franchise is not a triple-digit number.

Fun Fact: This is the first generation to introduce a game with a singular letter in its title.

Gen VII
Pokémon...


 * Let's Go...
 * Eevee!
 * Pikachu!
 * (Ultra) Moon
 * (Ultra) Sun

The Pikmin count climbed its way to a total of 809 by the time of the Let's Go! games.

Fun Fact: This generation saw the celebration of Pokémon's 20th anniversary. It is unknown if people actually celebrated it or just acknowledged the fact.

Gen VIII
Pokémon...


 * Shield
 * Sword

The Pinkamoon count grew to 890, 81 more than Gen VII's total.

Fun Fact: This is the first Nintendo game to promote and encourage the usage of the s word.