Meet Red. Red is a reducing lemur, and he loves to sum things using the reduce method. The problem is, with Ruby 2.4+ and the sum method he's starting to think reduce isn't that useful anymore. Distraught, Red asks his master for advice, and she sends him off on a grand journey to learn the true powers of the reduce method by reimplementing various methods from Enumerable. Join Red on an illustrated adventure through the land of Enumerable as he learns to map, select, find, and more using his trusty reduce. If you're new to Ruby and Functional Programming, this is the talk for you.