The very short answer:
Evariste Galois was a precocious mathematical genius killed before he was 21 years old in a duel in 1832 but whose scattered writings (less than 200 pages in all) which, when published 14 years after his death, opened up a new branch of mathematics known as group theory, which underpins much of modern mathematics, with many applications in modern physics, in particular nuclear physics.
A little longer answer:
By abstracting equations and looking at their solutions in terms of groups, Galois was able to determine their solvability. He wasn't concerned with finding particular solutions, but in the more fundamental question of determining 'a priori' whether or not solutions existed.
Overlooked in his lifetime, Galois' discoveries were eventually brought, by Galois' brother, to the attention of the mathematician Joseph Louisville, who published his papers in 1846 and announced a new, fertile area of mathematics. The importance of Galois' work is clear from the tribute paid to him by Camille Jourdan, who, in 1870, published a 600-page mathematical text which he considered nothing more than a footnote to Galois' work.
In this century, Galois' seminal discoveries have continued to inspire researchers. A branch of mathematics, Galois Theory, has been named after him. His Group Theory approach to algebra has led to the recognition of structure as an important aspect of contemporary mathematics. Like so much of pure mathematics, his abstract theories have been used to make advances in applied areas such as crystallography, genetics and nuclear physics. A few years ago Andrew Wiles put forward a solution to Fernat's 'Last Theorem', which had baffled mathematicians for almost 400 years. The 200-page proof would not have been possible without Galois Representations.
Do not believe every thing you read, on the internet and elsewhere, about Evariste Galois. There are many "Evariste Galois Myths" and Tony Rothman's essay tries to set the record straight. If you cannot find Tony Rothman's essay at the University of Texas, get it here.
On the outside chance you want to learn about the exact role of Evariste Galois in the developpment of group theory, here is a useful link.
Now that you know who was Evariste Galois, I will tell you why our Westsail 32 was named "E Galois"
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