Dr. Euler's Fabulous Formula: Cures Many Mathematical Ills

What are e, pi, and i, and who was Euler? Now, it is hard for me to believe that there are any literate readers in the world who haven't heard of the transcendental numbers e = 2.71828182... and pi = 3.14159265..., and of the imaginary number i. As for Euler, he was surely one of the greatest of all mathematicians. Making lists of the "greatest" is a popular activity these days, and I would wager that the Swiss-born Leonhard Euler (1707-1783) would appear somewhere among the top five mathematicians of all time on the list made by any mathematician in the world today (Archimedes, Newton, and Gauss would give him stiff competition, but what great company they are!).