This document provides an overview of the cognitive theory of multimedia learning. It discusses that cognitive theory centers on building meaningful connections between words and pictures for deeper learning. The three key elements of cognitive theory are the active processing assumption, dual channel assumption, and limited capacity assumption, which led to cognitive load theory. Cognitive load theory describes the three types of cognitive load: extraneous, intrinsic, and germane. The document then outlines the 12 principles of multimedia learning, which are strategies to reduce cognitive load by avoiding overstimulation. The principles are grouped according to the three cognitive load types.