The in-practice ”How”.
A business process is ”a series of actions that are needed in order to do something or achieve a result”. (Cambridge dictionary)
A workflow is “the way a particular type of work is organised, or the order of the stages in a particular work process”. (Cambridge dictionary)
A formalised way to repeat a series of actions again and again by following a series of steps, often graphically presented with some kind of business modelling technique, e.g. BPMN or Flowchart, in order to accomplish a controlled, repeated result. (Wikipedia)
An example of a process visualised with BPMN:
A Flowchart visualisation:
In order to be able to have effective processes an organisation needs to have a Business Process Management (BPM) office in place. The BPM office team decides what model should be used for mapping processes, and is responsible for the tools needed.