From: Anthony T. Holdener (2008) Ajax: The Definitive Guide, Sebastopol: O’Really
The usability of an AJAX Web application refers mainly to how easy the application is to navigate and manipulate, and how intuitive it is to the end user. If an application is usable, it is
- Structured … organised in meaningful and useful ways. Related parts of a page are placed together and unrelated parts are separated, based on a clear model that the user recognises…
- Simple… common tasks should be easy to accomplish. Communication between the application and the user should be basic in nature, avoiding technical and complicated language and jargon.
- Tolerant … flexible in how they handle mistakes … allows for easy cancelation and backtracking of user submissions and navigation… gracefully handles incorrect user input, and does not break or produce errors from such cases. Most important, tolerant Web applications make every effort to prevent most errors from reaching the user, and instead make reasonable assumptions about user intent and act accordingly.
- Reusable … reduces the amount of information the user needs to remember and rethink each time she reacts to a pge or control on the application. Consistent navigation tools, site structure, naming conventions, and so on allow the user to navigate the application without stopping to think about every action. Being reusable boils down to being consistent.
- Receptive … of user feedback – whether it takes the form of criticism, suggestions, or praise. … A receptive developer (…) thinks about the user, and designs with that user in mind.
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You should follow these six principles when designing Ajax Web Applications:
- Minimalist and aesthetic structure (Personal Comment: What is an aesthetic structure???) … An application’s structure is the most important aspect of its usability.
- Flexibility and efficiency
- Documentation and Help
You should ahere to the following four factors when designing an applications’s page layout
- Focal point