What are the three elements that make up a workflow?

Workflows consist of three elements – states, commands and actions1. A workflow state defines the status of an item in a workflow, such as Draft, Awaiting Approval, or Published. A workflow command defines the transition from one state to another, such as Submit, Approve, or Reject. A workflow action defines the operation that is performed when a command is executed, such as sending an email notification, validating an item, or publishing an item. Workflows can contain any number of workflow states and be as simple or complex as required. Items do not necessarily have to move through all the workflow states that you have defined. Some states can be optional or only applicable to certain kinds of content1. References:

Workflows and the Workbox