 In Section 2, the general theory of CA is explained, together with a selection of computational and complexity-theoretic results in the field. Section 2.1 provides a fourfold schematic definition of CA. Sections 2.2–2.3 explain the classification of one-dimensional CA proposed by Stephen Wolfram. Section 2.4 introduces the Edge of Chaos hypothesis, a key CA-related conjecture in complexity theory. Sections 2.5–2.7 generalize to automata occupying more than one spatial dimension, and/or relaxing some parameters in the definition of 2.1. We focus on the Game of Life—possibly the most popular CA—and its computational capabilities. 