These are the definitions of the labels that (as a general rule) start with a capital letter (lower case labels represent more general classes of posts).
Affordance: The nature of an interface such that it is obvious how it functions, based on natural or cultural conventions.
Ambiguity: A problem where the meaning or requirements for using a feature are not clear or straight-forward; one of multiple paths may be taken and it is not immediately obvious which path(s) might be correct. Forgiveness is one counter to this type of issue.
Asynchronicity: The nature of connecting and waiting for a response. There may be a delay between the time is request is made and the reply occurs. How the delay is handled impacts users' attitudes, since they do not necessarily know what is happening behind the scenes.
Click-thru: The number of clicks, presses, passes, scrolls or paths it takes to get from a starting point to an expected destination. In general, the more commonly used a feature is, the easier it should be to get to.
Cognitive Dissonance (CD): The sense of disconnect or wrongness of a system when an event occurs outside the user's expectations or experience. New systems will often cause cognitive dissonance due to unfamiliarity, but this will fade over time and use if properly designed. However, certain types of designs cause CD regardless of familiarity; these problems need to be avoided.
Consistency: Simply put, the use (or display) of similar components in similar ways across a given a system.
Convention: The expectation of how a feature or system should work based on agreement, standards, historical or traditional sources.
Disclosure: Exposure of a feature or an element based on its utility to the user. In simple systems, a user should be given as much up-front information as possible in order to alleviate any need to search for answers to straight forward questions. In more complex systems, a user should be give relevant information as soon as possible, usually before an action is actually taken, so that there is a limit in user errors.
Discordant Association (DA): The sense of disconnect that exists between two or more elements that otherwise should be related to one another.
Fitts' Law: The time it take for a user to touch a location increases with distance and with a reduction in smaller target size (simplistic definition).
Forgiveness: Allowing a user to input data or use a feature in a number of reasonable ways that prevent any negative consequences to the user (like error messages) and still allow for good functionality.
Least Surprise/Astonishment: The behavior of an arbitrary system should align with the expectations of a user. There should be no assumptions on the part of the designer that the user understands the internal nature of the interface. Any sort of state change should be reasonably associated with a given action, and consistent over time.
Overloading: The design pattern by which an interface can perform different actions depending on the mode of access or how the user interacts with the interfaces. Typically used to reduce the number of physical buttons on a screen or console, but has the side affect of creating cognitive dissonance if the user is not sure what mode the interface is in or how to access alternate features.
Txtspk: A writing pattern that takes shortcuts to reduce
the number of keystrokes and/or characters required in a message.
Typically used in text and instant messaging. Should be avoided in
articles and documents where professionalism is expected.
Useful Space: The outlook that space -- the empty regions between functionality -- possesses a useful quality, either practically or aesthetically. Space should occur as a part of the design, not as an afterthought or as a leftover result.
