Microtransactions

Microtransactions are payments of real money that players can use to advance further within a game, or to acquire vanity items. Microtransactions are usually implemented in mobile games, but they can serve as part of the income for free-to-play online games, such as Star Trek Online or RIFT.

The presence of microtransactions does not automatically mean that they are needed to complete the game, but it is often observed that they reduce the time needed to get to later stages of the game.