A task refers to a series of actions to achieve a goal. This may be at various levels from the keystrokes needed to save a document, to the steps taken to book a holiday. Tasks may be organised hierarchically in some forms of task model. Tasks are usually of fairly limited time from a few seconds to an hour with motor-level actions such as pressing a single key the smallest level considered and rarely extending to consider extended episodic interaction over days or longer. However, often tasks may be viewed as being part of a longer term activity or role.
Used in glossary entries: activity, extended episodic interaction, goal, role