Match Three Game

A Casual Video Game sub-genre that is Exactly What It Says On the Tin. The object is to match three objects of similar color/shape/species to eliminate said objects from the playing field. Specific objectives vary from game to game, but include:
 * Play until you run out of time or space.
 * Match a certain amount of Object X to advance
 * Rack up a certain amount of points to advance

Games may also throw special blocks onto the field, such as power ups, garbage blocks (which you can eliminate only by matching three other objects connected to it), obstacles (like garbage, but indestructible) and other bonuses. You can also — again, depending on the game — get bonus points and/or helpful effects by matching four or more objects.

Match Three Games came about during the heyday of the 1990s handhelds — specifically with the advent of Columns for the Sega Game Gear. With the boom in Casual Games, the genre has similarly expanded.

Examples:

Falling pieces
The player must control each piece as it falls from the top of the screen, moving it around and usually rotating it or shifting parts of the piece. A few have pieces arrive from some other direction, but the principle is the same.
 * Columns (1989; the Ur Example)
 * Magic Jewelry (Its NES bootleg)
 * Klax (1989; possibly tied for Ur Example)
 * Dr. Mario (match four)
 * Lumines (match a 2x2 square)
 * Puzzle Fighter
 * Puyo Puyo (match four)
 * Taisen Puzzle Dama and its numerous sequels and themed Spin Offs:
 * Susume! Taisen Puzzle Dama
 * Twinbee Taisen Puzzle Dama
 * Tokimeki Memorial Taisen Puzzle Dama and Tokimeki Memorial 2 Taisen Puzzle Dama
 * Tsuyoshi Shikkari Shinasai Taisen Puzzle-Dama
 * Chibi Maruko-chan Taisen Puzzle Dama
 * Pop'n Taisen Puzzle Dama Online
 * Tetris 2 (can best be described as Dr. Mario with Tetris pieces)
 * Wetrix
 * Yoshi (match two)
 * Critical Mass has you manually place the blocks on a cube that gradually expands, but the spirit is the same.
 * Blastris B, one of the six games sold with the Super Scope.
 * Bomberman: Panic Bomber
 * Hatris (match five)

Swapping pieces
The player has to swap two or more pieces. As blocks are cleared, the field is replenished with more pieces, either immediately after they're cleared or continuously from some source.
 * Bejeweled (Trope Codifier, what a lot of people think is the Ur Example). The first ever was called Shariki, developed by Russian programmer Eugene Alemzhin for DOS in 1994.
 * Cradle of Rome
 * Gyromancer
 * Henry Hatsworth in The Puzzling Adventure
 * Hexic
 * Jewel of Atlantis
 * Jewel Quest
 * Legend of Fae, a hybrid of this and a simple side-scrolling RPG
 * Panel De Pon, a.k.a. Tetris Attack
 * Pokémon Puzzle League
 * Puzzle Quest Challenge of the Warlords
 * Puzzle Quest: Galaxtrix
 * Puzzle Kingdom
 * Puzzle Chronicles
 * Puzzle Quest 2
 * Sally's Quick Clips is a combination of piece-swapping Match Three and a Time Management Game.
 * Taisen Tokkae Dama, the "swapping pieces" sister series of Taisen Puzzle Dama
 * Tokimeki Memorial Taisen Tokkae Dama, themed Spin-Off of the original TTD game
 * Yoshi's Cookie (match five)
 * Zoo Keeper

Swapping and Falling
The player has to swap two or more pieces. However, blocks also come down from the top of the screen at the same time. There is limited control in where and how falling pieces will land.
 * Meteos
 * Pokémon Trozei! (match four; a hard mode requires the player to match five)

Launching pieces
The player controls the direction or location each piece will go before they start moving. Once a piece starts moving, it travels in a straight line and is out of the player's control.
 * Magical Drop
 * Magnetica
 * Puzzle Bobble a.k.a. Bust a Move
 * Snood
 * Tetrisphere
 * Bubbles (browser game requiring Flash).
 * Bubble Witch Saga, a Bubbles spinoff.

Other
The mechanics in these games don't fit in any category above or are unique.
 * Chromashift, which uses a relatively unique game mechanic, in that you change the color of the gems, instead of moving the gem positions..
 * "It is the nineties, and there is time for... Klax." This popular arcade game featured falling colored tiles, which were to be placed in "klaxes" (rows, columns, or diagonals of same-colored tiles) in a 5×5 grid. The real challenge was that building complex formations that yielded big points, as klaxes made other tiles fall into scoring positions. Tiles could also be thrown back. Memorable for its quirky look and feel.
 * Similar to Klax is Audiosurf, which combined the concept with levels generated from your music files.
 * Wrecking Crew '98: Each row of panels can be shifted, though unwanted panels can usually be demolished individually.

Uncategorized

 * 7 Wonders
 * Big Kahuna Reef
 * Bounce Out!
 * Chuzzle
 * Fruit Smash and its seasonal sequel, Trick or Treat Smash
 * Glissaria (match five)
 * Mariposa
 * Molesting the Match-3 Market
 * Puzznic (match two)
 * Tip Top
 * The Bilge Pumping and Rumble games in Yohoho! Puzzle Pirates. The Sailing game also has a match-four mechanic, but it's not the primary goal.
 * The developers at Three Rings really like these; the Foraging and Treasure Haul games are also Match Three.
 * As an April Fools' Day joke, Kongregate featured a Match One game.
 * Paris Hilton's Diamond Quest. Really.
 * Zuma from the Xbox Live Arcade.