sentences:  Variable demands on workflows were recognised when the theory of critical paths and moving bottlenecks was considered.A workflow management system (WfMS) is a software system for setting up, performing, and monitoring of a defined sequence of processes and tasks, with the broad goals of increasing productivity, reducing costs, becoming more agile, and improving information exchange within an organization.These systems may be process-centric or data-centric, and they may represent the workflow as graphical maps.