Graphene-based nanomaterials are in the forefront of chemical research. This tutorial review provides an introduction to their electrochemistry, its fundamentals and applications. Selected examples of applications in energy storage and sensing are presented. The synthetic methods for preparing graphenes as well as their materials chemistry are thoroughly discussed, as they have a profound influence on the electronic and electrochemical behavior of graphene-related nanomaterials. Inherent electrochemistry and spectroelectrochemistry of graphene nanomaterials is discussed thoroughly. Important application in sensing and energy storage areas are highlighted.