Some background, for those unfamiliar with this area. Algebraic geometry grew out of the study of solutions of systems of polynomial equations. This is naturally a question of geometry, which can be studied analytically (using tools from calculus, for example). If you are willing to consider solutions over the complex numbers, and not just the real numbers, you can study the question algebraically, as well. Once you take that step, you can ask what happens when you look at solutions over exotic objects such as finite fields or rational functions.

Alexander Grothendieck pushed for a very general formulation of this algebraic approach, using the notion of "scheme". Together with Jean Dieudonne, he wrote an introduction to this topic, called EGA, which is French for "Elements of Algebraic Geometry". This is one of the foundational texts in algebraic geometry now.

At some point, Grothendieck became disillusioned with both mathematics and academia, quit both, and isolated himself from most people. Not long before his death, he expressed the desire that all of his work cease to be published. He died 5 years ago now, and I'm not actually sure of the legal status of republishing his work, though people are determined to go ahead because of its great historical significance. While I think EGA has largely been superseded by newer sources, some of his later work (known as SGA) has not.