Here, we familiarize the reader with the main theme. How is it possible that the formulas of ancient Greek mathematicians are perfectly fitted for our technology that was just recently invented? We show of several concrete and well-known examples, where an obscure, ancient, mathematical idea reappears in modern science and technology: ellipses, imaginary numbers, trig formulas, and such. At the end of the chapter, the reader is “hooked” and he/she believes that there is a mystery to be solved.