Civilization

Civilization is a series of turn-based strategy video games, first released in 1991. Sid Meier developed the first game in the series and has had creative input for most of the rest, and his name is usually included in the formal title of these games, such as Sid Meier's Civilization VII. There are seven main games in the series, a number of expansion packs and spin-off games, as well as board games inspired by the video game series. The series is considered a formative example of the 4X genre, in which players achieve victory through four routes: "eXplore, eXpand, eXploit, and eXterminate". Many of its installments have been cited as amongst some of the greatest video games of all time.

All titles in the series share similar gameplay, centered on building a civilization on a macro-scale from prehistory up to the near future. Each turn allows the player to move their units on the map, build or improve new cities and units, and initiate negotiations with the human or computer-controlled players. The player will also choose technologies to research. These reflect the cultural, intellectual, and technical sophistication of the civilization, and usually allow the player to build new units or to improve their cities with new structures. In most games in the series, one may win by military conquest, achieving a certain level of culture, building an interstellar space ship, or achieving the highest score, among other means. Later games have introduced gameplay concepts and victories based on religion, economics, and diplomacy. Meier had adapted an approach for each new title so that it contains a third of existing features, another third that are improvements from the previous game, and the remaining third as introducing new features. Newer games often include extendable downloadable content that adds to that game, and often will become part of the new features in the next main game of the series.