A breakdown of the required information and actions needed to achieve a task. Helps designers and developers understand the current system and its information flows. Makes it possible to allocate tasks appropriately within the new system.
Task analysis refers to the broad practice of learning about how users work (i.e., the tasks they perform) to achieve their goals. Task analysis emerged out of instructional design (the design of training) and human factors and ergonomics (understanding how people use systems in order to improve safety, comfort, and productivity). Task analysis is crucial for user experience, because a design that solves the wrong problem (i.e., doesn’t support users’ tasks) will fail, no matter how good its UI.
In the realm of task analysis, a task refers to any activity that is usually observable and has a start and an end point. For example, if the goal is to set up a retirement fund, then the user might have to search for good deals, speak to a financial advisor, and fill in an application form — all of which are tasks. It’s important not to confuse goals with tasks. For instance, a user’s goal isn’t to fill in a form. Rather, a user might complete a form to register for a service they want to use (which would be the goal).
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Hierarchical Task Analysis
In its most basic form, a hierarchical task analysis provides an understanding of the tasks users need to perform to achieve certain goals. You can break down these tasks into multiple levels of subtasks. In user experience, you can use hierarchical task analysis to describe the interactions between a user and a software system. When designing a new system, hierarchical task analysis lets you explore various possible approaches to completing the same task. When analyzing an existing system, it can help you to optimize particular interactions.
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