Category theory
Category theory is a branch of mathematics that deals with structure, rather than with particulars. It deals with the kinds of structures that make programs composable.
Category theory is a branch of mathematics that is similar to Set theory. A basic example of a category is the category of sets, where the objects are sets and the arrows are functions from one set to another. Objects of a category need are typically sets, and arrows are typically functions. Any way of formalizing a mathematical concept so that it meets the basic conditions on the behavior of objects and arrows is a valid category.
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I could not find an easy-to-understand resource for learning category theory. Most of what's out there is geared toward mathematicians. Though I did take a good number of advanced math classes in college, I am not a practicing mathematician. While understanding the logical and mathematical formalism is important (and we'll cover the enough to be conversant), what I really wanted...
