"A workflow engine can be used to perform task management between users, assigning tasks to users based on a number of criteria, and tracking their time to complete assigned tasks.  In this arena there is also the concept of escalation - who should be notified and how if a user fails to complete a task in a certain timespan.

 

System integration is also aided by a workflow engine in that it can be used to orcestrate diverse processes in an enterprise, functioning as a robust middleware component that performs all communications between disparate systems.  Using a workflow engine in this way, and for orcestration in an ESB allows platform agnostic message routing and the externalizing of rules from the nornal point to point integration efforts that are often seen.  Many more developers became aware of workflow in the enterprise with the ratification of the BPEL language specification and its implementations.

 

An application can be made much more extensible and customizable by embedding a workflow engine as well.  If architects provide "hooks" in a system that are executing processes, users and future developers can extend or integrate an existing piece of software by modifying the processes rather than the source code.  This can make an application more robust over time, as it can be integrated via a process hook mechanism that does not modify the original, core functionality of the system.  This can aid in faster integration times, and less errror prone extension.

 

If a workflow engine is embedded in a web application framework that allows it, it can be used to perform the routing of the page flow in a web application.  this has the added benefit of a single unified modeling language/environment for application logic as well as page flow.  Additionaly, the engine's exception handling mechanisms can be employed to sometimes respond to errors in a more robust fashion.

 

When a graphical process designer is utilized, a workflow system can be used to more easily visualize the the paths of execution in a system, allowing business users more visibility into the process without developers always having to resort to UML sequence/flow diagrams.  this has the side benefit of the modeled workflow being something of an "executable model" - something we've been after in the development community for some time."