A little history lesson today. Have you ever used a compiler? Written an algorithm? Used the search function inside a document? Then chances are you've used work by Donald Knuth. For the last 60-odd years he's been learning, teaching, doing, and writing about computer science and it's fundamentals.
By far his greatest contribution to the field is his magnum opus, The Art of Computer Programming. It was originally going to be one book, but it's up to 4 volumes now and growing. It covers everything from fundamentals search/sort, numerics, combinatorics, data structures, and more.