The cytoskeleton is an interconnected network that provides support and organization to cells. In eukaryotes, its main components include actin and microtubules, two types of dynamic filaments. In addition to carrying out structural roles, these filaments act as tracks for the movement of molecular motors that convert chemical energy into mechanical work as they transport and/or anchor organelles, vesicles and other intracellular components. Kinesin and dynein motors both utilize microtubules for transport, whereas myosins–which are the focus of this Cell Science at a Glance article–are the only known actin-based motor proteins (Goode et al., 2000; Hartman et al., 2011; Ross et al., 2008). Different members of the myosin family are typically denoted by roman numerals, such as myosin II and myosin V; to ensure consistency between the accompanying poster and the text, we refer to them here as M2 (or class 2) and M5 (or class 5), respectively. The myosin superfamily is a large and diverse protein family, and its members, which are grouped into many classes (Foth et al., 2006; Odronitz and Kollmar, 2007), are involved in a number of cellular pathways (Krendel and Mooseker, 2005; Woolner and Bement, 2009). We first describe the basics of myosin mechanoenzymology and motility. Next, we discuss myosin–cargo interactions and present a summary of the roles of myosin proteins in cells, focusing on actin-based projections and the endomembrane system. Finally, we provide an overview of the diseases associated with myosin mutations and our perspective on the future of the myosin field. In order to provide a general overview of the myosin family, we will not be able to discuss some aspects of the vast and important literature on myosins. For example, we will not focus on the large body of literature on yeast myosins, as it deserves a rather long review on its own.