From The Art and Popular Culture Encyclopedia
The Culture is a fictional interstellar post-scarcity civilisation or society created by the Scottish writer Iain M. Banks and features in a number of his space opera novels and works of short fiction, collectively called the Culture series.
In the series, the Culture is composed primarily of sentient beings of the humanoid alien variety, artificially intelligent sentient machines, and a small number of other sentient "alien" life forms. Machine intelligences range from human-equivalent drones to hyper-intelligent Minds. Artificial intelligences with capabilities measured as a fraction of human intelligence also perform a variety of tasks, e.g. controlling spacesuits. Without scarcity, the Culture has no need for money; instead, minds voluntarily indulge humanoid and drone citizens' pleasures, leading to a largely hedonistic society. Many of the series' protagonists are humanoids who choose to work for the Culture's elite diplomatic or espionage organisations, and interact with other civilisations whose citizens hold wildly different ideologies, morals, and technologies.
The Culture has a grasp of technology that is advanced relative to most other civilisations that share the galaxy. Most of the Culture's citizens do not live on planets but in artificial habitats such as orbitals and ships, the largest of which are home to billions of individuals. The Culture's citizens have been genetically enhanced to live for centuries and have modified mental control over their physiology, including the ability to introduce a variety of psychoactive drugs into their systems, change biological sex, or switch off pain at will.