What online trading system debuted in Pokémon Diamond and Pearl?

The Global Trade Station debuted in Pokémon Diamond and Pearl.

Often abbreviated as GTS, the system allowed players to deposit a Pokémon and request a particular species in return, or search for trades offered by other players. It connected Pokémon trading to the Nintendo Wi-Fi Connection, expanding the series beyond local link cables and nearby friends.

Diamond and Pearl were released for Nintendo DS in Japan in 2006 and internationally in 2007. They introduced the Sinnoh region, the fourth generation, and new species such as Turtwig, Chimchar, Piplup, Dialga, and Palkia. The games also expanded online battles and communication features.

GTS is sometimes confused with Wonder Trade, which gives a player a random Pokémon, or Pokémon Bank, which is cloud storage rather than a trading marketplace. The Player Search System arrived later in Pokémon X and Y and provided a broader interface for online interactions.