There are many different types of work. For example: baking bread, making a bed, designing a house or collecting survey results to compile a statistic. In all of these examples, we can see the one tangible ‘thing’ which is produced or modified: the bread, the bed, the house or the statistic. In this book, we shall call such a ‘thing’ a case. Other terms used are work, job, product, service or item. A case does not need be a specific object; it can also be more abstract - like, say, a lawsuit or an insurance claim. A building project or the assembly of a car in a factory are also examples of cases.

Working on a case is discrete in nature. That is, every case has a beginning and an end, and each can be distinguished from every other case. Each case involves a process being performed. A process consists of a number of tasks which need to be carried out and a set of conditions which determine the order of the tasks. A process can also be called a procedure. A task is a logical unit of work which is carried out as a single whole by one resource. A resource is the generic name for a person, machine or group of persons or machines which can perform specific tasks. This does not always mean to say that the resource necessarily carries out the task independently, but that it is responsible for it.

Worklist handler
A workflow management system ensures that work items are allocated to resources. If a work item is allocated to a person, it appears in their (actual or metaphorical) in tray. This always contains a list of those tasks still to be performed. By selecting a work item from the in-tray, the person can carry out that task. Note that a work item may appear in more than one in tray.

Synonyms:
• work tray;
• in-tray;
• worklist;
• to-do list.

Bron: Workflow Management, Models, methods and systems, Wil van der Aalst & Kees van Hee (PDF)