Karel Čapek (Czech: [ˈkarɛl ˈtʃapɛk]) was a Czech writer, playwright, critic, and journalist, renowned for his contributions to the science fiction genre. He is best known for his novel War with the Newts (1936) and play R.U.R. (Rossum's Universal Robots) (1920), the latter introducing the word "robot" to the world. Čapek's works often contained politically charged themes that dealt with the social turmoil of his time. Influenced by American pragmatic liberalism, he was a fervent advocate for free expression and vehemently opposed the rise of both fascism and communism in Europe.

Though nominated for the Nobel Prize in Literature seven times, Čapek never won the award. However, his legacy is commemorated through several awards, including the Karel Čapek Prize, which is given by the Czech PEN Club for literary work that contributes to reinforcing or maintaining democratic and humanist values in society. He also played a key role in establishing the Czechoslovak PEN Club as a part of International PEN.

Čapek was a prominent figure in the humanist, pragmatist, and liberal democratic movements of his era, epitomized by the first Czechoslovak president Tomáš Masaryk. His works, such as The Absolute at Large (1922) and War with the Newts, are celebrated for their fine irony, satirical stance on Nazism, and philosophical and political background. In addition to his literary achievements, Čapek is remembered for his contributions to journalism, collaborating with publications like Lidové noviny.

As one of the most influential Czech writers of the 20th century, Čapek wrote with intelligence and humor, covering a wide variety of subjects. His work is known for its insightful and precise descriptions of reality, and he is acclaimed for his mastery of the Czech language. His untimely death at the age of 48 left a profound impact on the literary world, prompting George Bernard Shaw to remark, "Why him? Why not me?"