B.

Reading

Task 2. Read the text and compare your answers to question 3 in Task 1.

User Interface Guidelines

When designing a user interface, there are some basic principles and guidelines that you should adhere to. Most of these are common sense, but some may not be so obvious. The following list summarizes the main guidelines to be aware of. Note that these are not presented in any particular order.

• Meet the user’s expectations — An application that enables a user to perform a specific task should function the way the user would expect. If you meet the user’s expectations, he will be comfortable using the interface.

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•Keep the interface clear and simple — An interface’s appearance should convey its function in an obvious manner and allow easy navigation from one part of the interface to another. Simple and clear interfaces don’t distract the user’s attention from key tasks. Group related controls together but avoid areas with a high density of controls. Also, ensure that controls that receive mouse input are of a reasonable size; this encourages error-free navigation. Similarly, don’t have very large distances between frequently used controls. Both situations will make the user tired, the first because excessive concentration is required and the second because excessive mouse movement is required.

•Make the interface intuitive and familiar to use — Try to make it possible for users to figure out how to perform a task without having to be taught. Few users will be totally familiar with your interface, so you are guaranteed that at some time they will come across something unfamiliar. If this happens early in the learning process and the user cannot overcome his lack of knowledge, he may choose not to use your application. On the other hand, if you provide users with an intuitive interface, they will learn how to use it in less time and experience the more advanced capabilities of your application sooner. This is important when a user is trying to identify how powerful your application is and whether or not it is suitable for his needs. An additional consideration is to ensure that tasks in your interface are logically sequenced; in other words, your interface should function in an order that makes sense to the user. This will help make the user feel comfortable with your application.

•Keep the interface friendly — If you provide the user with a friendly interface, he won’t mind spending time learning and using it. If the user spends more time doing something, he will become more accomplished at it. A willingness to spend time using an interface that is familiar and intuitive will affect the learning curve of your application, allowing productive use in as short a time as possible.

•Provide the user with feedback — Providing feedback to the user can help build his confidence and reassure him of what he is doing. It can also help keep the user’s interest when mundane or long tasks are being carried out. This is a very important facet of any interface, and you should endeavor to provide feedback that is as useful and accurate as possible. Feedback can take many forms, some of which are taken for granted, such as a button that looks pressed when it is clicked. Details such as these should not be considered optional. At a more fundamental level, your whole interface is feedback for the user. By adding extra feedback, you simply enhance what the user already experiences. In some cases, additional feedback may be

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essential, such as when the user has some form of disability (the subject of the next point).

•Make your interface as accessible as possible — This means providing varied types of feedback and varied forms of input to meet the needs of users who may have difficulty with normal approaches. For example, you could provide additional audio feedback for users with impaired sight, or you could provide speech recognition–driven input for users who have difficulty manipulating the standard input devices.

•Provide help — Sometimes a user will get stuck. To cope with this, you can do two things: Provide useful documentation and provide support. You should always provide some form of documentation for your application, as either online help or printed documentation. If possible, you should also provide some form of support. The kind of support you provide can range from simple email-based support to 24-hour manned support, either telephone-based or on-site. Providing at least email-based support should be considered mandatory.

•Allow customization — Let the user customize the interface to his liking. Simple things such as choice of color can have a significant effect on whether a user likes an interface. The use of system colors, such as clMenu (for menus), can help your interface take on an appearance the user likes. But customization is not just letting the user move things around so the interface looks good. It is about allowing the user to access functionality that he uses frequently in a way that is most convenient for him. Not everyone will use your application in the same way. Allowing a user to modify the interface to reflect his normal usage patterns can help make your application become the user’s preferred tool.

•Provide an escape route for the user — Even the most experienced user will take a misstep. Provide some form of escape to let him backtrack. In its most common form, this means providing an undo function, which is now almost a standard feature of all editing-type interfaces.

•Inform the user of errors in an understandable way — No matter how foolproof you might think your interface is, some user somewhere will cause an error to occur. When that happens, the normal response is to display a message box to the user indicating what the error is and how to avoid it. Sometimes you may even give the user a second chance to complete the operation that caused the error. One of the single most annoying things to do in this situation is to display a message box that provides only a cryptic message that even the developer may not understand. From the user’s point of view, the interface will appear broken, and this is certainly not a comfortable feeling. You should therefore endeavor to provide constructive information regarding any errors that may

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