Dispersion forces are ubiquitous in chemistry, yet they are often misunderstood. This article provides background into why they are called dispersion forces and explains how to describe them in terms of time-independent quantum mechanics. The article also describes the breakdown of the multipole series that is often used to describe dispersion forces, and it comments on the representation of dispersion forces in molecular mechanics. In general, the article tries to provide a proper framework for understanding and describing dispersion forces.