The Acts of the Apostles (Ancient Greek: Πράξεις τῶν Ἀποστόλων, Práxeis tōn Apostólōn; Latin: Acta Apostolorum), usually referred to simply as Acts, is the fifth book of the New Testament; Acts outlines the history of the Apostolic Age. The author is traditionally identified as Luke the Evangelist; see Authorship of Luke–Acts for details.

While the precise identity of the author is debated, the consensus is that this work was composed by a (Koine) Greek speaking Gentile writing for an audience of Gentile Christians. The Early Church Fathers wrote that Luke was a physician in Antioch and an adherent of the Apostle Paul. It is said to be that the author of the Gospel of Luke is the same as the author of the Acts of the Apostles. Tradition holds that the text was written by Luke the companion of Paul (named in Colossians 4:14) and this traditional view of Lukan authorship is “widely held as the view which most satisfactorily explains all the data.” The list of scholars maintaining authorship by Luke the physician is lengthy, and represents scholars from a wide range of theological opinion. However, there is no consensus, and according to Raymond E. Brown, the current opinion concerning Lukan authorship is "about evenly divided."