Donald Norman’s Design Principles
Donald Norman claims that great design are based on all these categorize features which aimed the user’s behaviour, creating the best solutions.
Visibility – Refers to the basic functions of the system or product where easy enough for users to understand and use. All performance aspects of the product or system should be relatively obvious to the user. The functions should be evident just be looking at the device so the user can easily find out what to do next.
Feedback – Refers to some immediate and obvious kind of signal while using the product or system. These signals to inform user there was a response or a result, then allowing the person to continue with the activity. Sending back information about what action has been done and what has been accomplished. Various kinds of feedback are available, could be audio or visual cues or something that is obvious. The response must also make sense and let the user know if what they done.
Constraints – Refers to restricting the kind of user interaction, stopping users from taking certain actions that are not suppose to be taken with certain devices or take place at a given moment. There are various ways this can be achieved, such as physical, semantic, logical, and cultural constraints.
Mapping – Refers to the relationship on how the product is used and displayed. There should be a relation between actions and intentions on using all the product or system. A good mapping resulting ease of use of a system or product to the users.
Consistency – Refers to designing in similar ways and elements while achieve something. Users to ‘get used to a product or system’ and therefore once they learn how to use it, they can continue to use it because given actions produce the same results so it is consistent every time.
Affordance – Refer to an attribute of an object that allows users to know how to use or operate. To afford means “to give a clue” (Norman, 1988). When there are affordances of a physical object, it is easy for users to know how to interact with it.
Referring to Donald.A Norman’s ‘The Design of Everyday Things’ (2002)