You all know about him through the geometry you were taught at school, Euclidian Geometry. edit: I have to admit that I have not followed the developement of the Euclid telescope by ESA, I do know that it's a wide angle camera and presumably it is an ultra high resolution camera. I believe it takes images in a rotary fashion, I might be wrong and I think part of the purpose of the telescope is to rapidly map changes in its field of view. I'll read up on it, like all the telescopes that have been launched they are all designed to complement each other to explore different parts of the electromagnetic spectrum or in the case of Euclid to have a wider field of view. I'll read up on it.
Regards Euclidian geometry one of the most important parts was the paralell postulate the 5th postulate in Euclid's elements while not specifically mentioning paralell lines it was accepted that paralell lines would never converge on an infinite Euclidian plane, however it was later shown that there are other geometries known as Non Euclidian Geometries where paralell lines do in fact converge, Spherical Geometry which I had to study in my Astronomy classes at Glasgow University in the 1970s being the prime example, straight lines on a sphere converge think lines of longitude for example, people that study navigation also have to learn spherical geometry. Riemann Geometry which was key in Einstein's General Relativity is an example of a Non Euclidian geometry dealing with curved manifolds.
