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Why is the task being done?
Essential Task: The user needs to input character sequences. eg to search for show/movie, enter his username (XBox), or send messages, etc.
What does the user need to know or have before doing the task?
He needs to know how to get to the text entry field and how to insert/delete characters into it.
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How often is the task performed?
Text entry is relatively infrequent but quite an important part of these applications. If the user depends on search to find what he is looking for, the text entry field is on the application's critical path and significantly contributes to the user's overall satisfaction. Xbox users we observed often sent messages to each other.
What are its time/resource constraints?
Text entry is limited by (1) the size of the screen on which text entry widgets can be displayed (2) the controls available on the remote/controller (3) the user's patience (it shouldn't take more than a few seconds to type a few words.
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