Fadi FatayriFatayriitibarenLlanes, Asturias, İspanyaitibarenLlanes, Asturias, İspanya

Good overview of algebraic number theory as it applies to FLT, however not exactly pitched at beginners. You'll want to have a grounding in abstract algebra & linear algebra at the minimum. Still, even if you don't, you can get a good sense of the "big picture" and a high-level understanding of the advances in mathematics that were directly or indirectly related to attempts to solve FLT. Overall a fascinating read if you're a math geek who wants something a little deeper than Simon Singh's pop treatment of Wiles' proof.