Title: Ptolemy
Content:  Claudius Ptolemy (, Klaúdios Ptolemaîos, ; Claudius Ptolemaeus; c. 100 AD) was a mathematician, astronomer, astrologer, geographer, and music theorist, who wrote about a dozen scientific treatises, three of which were of importance to later Byzantine, Islamic, and Western European science. The first is the astronomical treatise now known as the Almagest, although it was originally entitled the Mathēmatikē Syntaxis or Mathematical Treatise, and later known as The Greatest Treatise. The second is the Geography, which is a thorough discussion on maps and the geographic knowledge of the Greco-Roman world. The third is the astrological treatise in which he attempted to adapt horoscopic astrology 
Title: Culture of Egypt
Content:  Ptolemy is one of the most famous astronomers and geographers from Egypt, famous for his work in Alexandria. Born Claudius Ptolemaeus (Greek: Κλαύδιος Πτολεμαίος; c. 85 &ndash; c. 165) in Upper Egypt, he was a geographer, astronomer, and astrologer. Ptolemy was the author of two important scientific treatises. One is the astronomical treatise that is now known as the Almagest (in Greek Η μεγάλη Σύνταξις, "The Great Treatise"). In this work, one of the most influential books of antiquity, Ptolemy compiled the astronomical knowledge of the ancient Greek and Babylonian world. Ptolemy's other main work is his Geography. This too is a compilation, of what was known about the world's geography in the Roman Empire in his time. In his Optics, a work which survives only in an Arabic translation, he writes about properties of 
Title: Ptolemy (name)
Content:  Ptolemy commonly refers to Claudius Ptolemaeus (ca. 90 AD–ca. 168 AD), a writer, geographer, mathematician, astronomer and astrologer who lived in the Alexandrine Greek culture of Roman Egypt.
Title: 4001 Ptolemaeus
Content:  This minor planet was named after 2nd-century Greco-Roman astronomer Ptolemy (Latin: "Ptolemaeus") by IAU's Minor Planet Names Committee. He is best known for his influential Almagest, a mathematical and astronomical treatise on the apparent motions of the stars and planetary paths. Its ideas dominated astronomy for 1200 years until Copernicus in the early Renaissance. The official naming citation was published by the Minor Planet Center on 21 November 1991 (M.P.C. 19335).
Title: Science in classical antiquity
Content:  Claudius Ptolemy (c. 100–170 AD), living in or around Alexandria, carried out a scientific program centered on the writing of about a dozen books on astronomy, astrology, cartography, harmonics, and optics. Despite their severe style and high technicality, a great deal of them have survived, in some cases the sole remnants of their kind of writing from antiquity. Two major themes that run through Ptolemy's works are mathematical modelling of physical phenomena and methods of visual representation of physical reality. Ptolemy's research program involved a combination of theoretical analysis with empirical considerations seen, for instance, in his systematized study of astronomy. Ptolemy's Mathēmatikē Syntaxis (Ancient Greek: Μαθηματικὴ Σύνταξις), better known as the Almagest, sought to improve on the work of his predecessors by building astronomy not only upon a secure mathematical basis but also by demonstrating the relationship between astronomical observations and the resulting astronomical theory. In his 
Title: Ptolemy
Content:  Ptolemy lived in or around the city of Alexandria, in the Roman province of Egypt under Roman rule, had a Latin name (which several historians have taken to imply he was also a Roman citizen), cited Greek philosophers, and used Babylonian observations and Babylonian lunar theory. In half of his extant works, Ptolemy addresses a certain Syrus, a figure of whom almost nothing is known but who likely shared some of Ptolemy's astronomical interests. The 14th-century astronomer Theodore Meliteniotes gave his birthplace as the prominent Greek city Ptolemais Hermiou (Πτολεμαΐς Ἑρμείου) in the Thebaid (Θηβᾱΐς). This attestation is quite late, however, and there is no evidence to support it. Ptolemy died in Alexandria around 168.
Title: Ancient Greek literature
Content:  form of a tour of Greece, starting in Athens and ending in Naupactus. The scientist of the Roman period who had the greatest influence on later generations was undoubtedly the astronomer Ptolemy. He lived during the 2nd century AD, though little is known of his life. His masterpiece, originally entitled The Mathematical Collection, has come to the present under the title Almagest, as it was translated by Arab astronomers with that title. It was Ptolemy who devised a detailed description of an Earth-centered universe, a notion that dominated astronomical thinking for more than 1,300 years. The Ptolemaic view of the universe endured until Copernicus, Galileo, Kepler, and other early modern astronomers replaced it with heliocentrism.
Title: Ptolemy
Content:  text on astronomy across Europe, the Middle East, and North Africa, and its author soon became an almost legendary figure: Ptolemy, King of Alexandria. The Almagest was preserved, like many extant Greek scientific works, in Arabic manuscripts; the modern title is thought to be an Arabic corruption of the Greek name Hē Megistē Syntaxis (lit. "The greatest treatise"), as the work was presumably known in Late Antiquity. Because of its reputation, it was widely sought and translated twice into Latin in the 12th century, once in Sicily and again in Spain. Ptolemy's planetary models, like those of the majority of his predecessors, were geocentric and almost universally accepted until the reappearance of heliocentric models during the scientific revolution.
Title: Ptolemy
Content:  Ptolemy's second most well-known work is his Geographike Hyphegesis (Ancient Greek: Γεωγραφικὴ Ὑφήγησις; lit. "Guide to Drawing the Earth"), known as the Geography, a handbook on how to draw maps using geographical coordinates for parts of the Roman world known at the time. He relied on previous work by an earlier geographer, Marinus of Tyre, as well as on gazetteers of the Roman and ancient Persian Empire. He also acknowledged ancient astronomer Hipparchus for having provided the elevation of the north celestial pole for a few cities. Although maps based on scientific principles had been made since the time of Eratosthenes (c. 276-195 BCE), Ptolemy improved on map projections. The first part of the 
Title: Ptolemy
Content:   Ptolemy's Mathēmatikē Syntaxis (Ancient Greek: Μαθηματικὴ Σύνταξις, lit. "Mathematical Systematic Treatise"), better known as the Almagest, is the only surviving comprehensive ancient treatise on astronomy. Although Babylonian astronomers had developed arithmetical techniques for calculating and predicting astronomical phenomena, these were not based on any underlying model of the heavens; early Greek astronomers, on the other hand, provided qualitative geometrical models to "save the appearances" of celestial phenomena without the ability to make any predictions. The earliest person that attempted to merge these two approaches was Hipparchus, who produced geometric models that not only reflected the arrangement of the planets and stars but could be used to calculate celestial motions. Ptolemy, following Hipparchus, derived each of his geometrical models for 

Question: who was ptolemy and what did he do?
Answer: Mathematician.