Euclid's birthplace and dates are not known, however his famous book, The Elements, is dated about 300 BC. There is little hard information about Euclid's life. He is thought to have studied in Athens at the school established by Plato, and therefore would have learnt his geometry from the students of Plato.
Euclid probably supported himself teaching geometry. He eventually moved to Alexandria where the greatest library in the ancient world was also the most important site of learning at the time. It is here that Euclid composed The Elements.
There are a number of stories about Euclid which may or may not be founded on truth. When King Ptolemy I of Egypt asked him for a short course in Geometry, he is reported to have replied that "there is no royal road to Geometry." Another story concerns a student who asked what was the use of learning Geometry. Euclid did not reply but instructed his servant to give the student a few coins since he must profit from all that he learns.
The Elements itself is not primarily an original work, rather it is a collection in which most of the mathematics known at the time is structured into a single whole. The Elements consists of 13 books that cover geometry as well as algebra. It is probably the most influential book after the scriptures, having undergone over 1000 editions, and it formed the basis of the secondary school mathematics curriculum up until the present century. The Elements presented succeeding generations with a supremely well organized example of the axiomatic method: the method by which a small number of undefined terms and assumed statements (axioms) are used to prove additional statements (theorems) building up a much larger body of knowledge.
Euclid also wrote a number of other books. Some of these expanded on The Elements while others covered such topics as conic sections, optics, mechanics, and music. None of these, however, compare in importance with the The Elements; for this book established the axiomatic method as the driving force behind mathematics down to the present time.