A workflow describes the route work takes through a business. A new job might move from enquiry to quote, to approval, to scheduling, to delivery, to invoice, with a named person or team responsible at each stage and rules about what happens next.
When a workflow is built into software, the system routes tasks to the right people, reminds them when something is overdue and records progress. Everyone can see where a job stands. It works best when it follows how the business really operates, which is why we map the process before building it.