Intro to workflow

A workflow is a sequence of steps or connected work stages and work activities performed by a person or a team, to accomplish a specific goal.  A sequential workflow is a workflow where each stage of the work is dependent on the preceding stage. In this case the completion of the activities on a preceding workflow stage controls the advancement of the work to the next workflow stage. The figure below represents a sequential workflow. In this book we use the word workflow as a synonym for sequential workflow.

Sequential workflow representation

A workflow typically has feedback loop between adjacent work stages. This is an effective mechanism to improve the workflow. The subsequent stage is the consumer of the work from the previous stage. Therefore, the subsequent stage is the best source of feedback for the work it consumes.

Workflow feedback loop

A manufacturing production line is an example of a workflow. The video below shows the Boeing 737 manufacturing line. In this example, the work (the aircraft under construction) slowly moves along an assembly line through all the work stages, where different activities are performed by a person or a team. Parts, equipment and tools are available at each work stage.  

The video for manufacturing the 737 Boeing depicts very clearly the workflow work and work itself. Currently the video is available at (search for “Boeing 737 manufacturing”).
Another example of workflow is the creation of an e-commerce website. This workflow would have stages such as analysis, coding, testing and deploying. These two sample workflows--the aircraft manufacturing and the e-commerce website creation--have different workflow representations. The aircraft is built on a physically moving assembly line. The working team, parts, equipment and tools are made available at the required workflow stages, and the item under production --the aircraft-- physically moves through the workflow stages. You can see the work as it moves along the workflow. On the other hand, the e-commerce website creation does not have physical parts moving along an assembly line. Yet it is still a workflow. For such cases, we can create visual representation of the work, and the workflow stages. The chapters to follow go in details on software development work stages, and visual representations of its workflow.