Leonhard Euler was undoubtedly the best mathematician of the eighteenth century. His contributions to mathematics range from common notation to the proof of the hypotheses of Newton and Leibnitz. His discoveries cannot be limited to just one field of interest, nor just to the field of mathematics. He made great strides in geometry, calculus, trigonometry, algebra, and number theory, as well as continuum physics, lunar theory, and other areas of physics. He is also one of the best-written mathematicians whose works could fit into 60-80 quarto volumes. Probably the most extraordinary fact about him is that most of the work he did occurred in the last twenty years of his life, when he was completely blind. Euler is undoubtedly one of the greatest mathematicians who ever lived. Leonhard Paul Euler was born the son of a shepherd on April 15, 1707 in Basel, Switzerland. Shortly after his birth, his family moved to Riehen, where Leonhard spent much of his childhood. Leonhard's father, Paul, was a good friend of the Bernoulli family, whose patriarch, Johann Bernoulli, was then considered Europe's leading mathematician. Bernoulli would ultimately have a major influence on Leonhard's life. When Leonhard was thirteen, he was sent to live with his maternal grandmother in Basel, where he enrolled at the University of Basel and eventually earned his Master's degree in Philosophy, and wrote his thesis comparing the philosophies of Newton and Descartes. Euler followed in his father's footsteps, studied theology, Greek and Hebrew and was determined to become a pastor. However, Johann Bernoulli was convinced that Euler was destined to become a great mathematician, and he convinced Paul Euler to let his son follow his passion... middle of paper... he was practically blind. This setback didn't slow him down because he managed to publish most of his work at this stage in his life, which is truly amazing. He got by thanks to his phenomenal memory, advanced mental calculation skills, and the help of scribes. Euler was truly unstoppable in the field of mathematics. As you can see, Euler gave a lot to the world of mathematics. From developing important notations, formulas, and constants, to proving formulas and equations that baffled most other mathematicians of his time, there was almost nothing he couldn't do that involved mathematics. He was an instrumental figure in developing the future of modern mathematics and is credited with contributing to the development of pre-calculus, calculus, and differential equations. Although not a household name, he is undoubtedly the greatest mathematician who ever lived.