The work known as the Almagest, named in Greek Μαθηματικὴ Σύνταξις (Mathēmatikē Syntaxis), and also called the Syntaxis Mathematica, is a 2nd-century Greek mathematical and astronomical treatise on the apparent motions of the stars and planetary paths, written by Claudius Ptolemy (Greek: Κλαύδιος Πτολεμαῖος, Klaúdios Ptolemaîos; c. AD 100 – c. 170). One of the most influential scientific texts of all time, its geocentric model was accepted for more than twelve hundred years from its origin in Hellenistic Alexandria, in the medieval Byzantine and Islamic worlds, and in Western Europe through the Middle Ages and early Renaissance until Copernicus.