Claudius Ptolemy’s circumstances of birth or family are not much known. But it is believed that he was born in Egypt, Roman Empire around 100 AD and that’s where he is believed to have lived and died. As deduced by his Latin name, He was of Greek descent. Ptolemy was a Greco-Egyptian astrologer, writer, astronomer and mathematician. During the 2nd century, he lived in Alexandria in the Roman province of Egypt and authored several scientific treatises, all of which were of academic importance with three being of considerable significance to the development of European, Islamic and Byzantine science in later centuries. Another one on geography gave a thorough discussion of the geographic knowledge of the Greco-Roman world. This treatise was used by Christopher Columbus (the Italian explorer) as the map for his path to Asia many centuries later. Ptolemy held Roman citizenship, lived in Alexandria and wrote in Koine Greek.
A renowned astronomer of his era, Ptolemy also authored the ‘Almagest’, the seminal text which is a treatise on the apparent motions of planetary paths and the stars. ‘Almagest’ is a highly influential scientific text whose geocentric model was accepted for more than 1200 years from its origin. Ptolemy adopted Hipparchus' solar model for drawing his models. This model consisted of a simple eccentric deferent. He inherited a geometrical toolbox from his Greek predecessors, and also a partial set of models for predicting where the planets would appear in the sky. He authored the ‘Cosmographia’ or the‘Geographia’, an important treatise on geography, called a treatise on cartography. In this treatise, he compiled the geographical knowledge of the 2nd century Roman Empire.