A manifesto is a written declaration of the intentions, motives, or views of the issuer, be it an individual, group, political party, or government. A manifesto can accept a previously published opinion or public consensus, but many prominent manifestos—such as The Communist Manifesto (1848) and those of various artistic movements—reject accepted knowledge in favor of a new idea. Manifestos relating to religious belief are generally referred to as creeds or confessions of faith.

The Italian word manifesto, itself derived from the Latin manifestus, meaning "clear" or "conspicuous". Its first recorded use in English is from 1620, in Nathaniel Brent's translation of the Italian from Paolo Sarpi's History of the Council of Trent: "To this citation he made answer by a Manifesto" (p. 102). Similarly, "They were so farre surprised with his Manifesto, that they would never suffer it to be published" (p. 103).