• Usability on the web is the ability of the user to navigate to find what they want. If they can't find it, they can't learn/use/disseminate it.

• You want people to be able to find answers.
• You want people to understand what they are doing, when they are doing it.
• Usability is a continual process, because technology is constantly developing.

Goals

• Make it fast, easy, and with the fewest errors.

• Minimize the intrusions on users' time.
• Meet the users' needs.

Attributes of usability

1. Utility
2. Learnability
3. Efficiency
4. Retainability
5. Errors
6. Satisfaction

Usability Engineering is an approach to product development that is based on user data and feedback. It involves direct observation and interactions with users to provide more reliable data than self-reporting techniques (i.e., focus groups, surveys and questionairres).

Usability Engineering begins in the concept phase with field studies and contextual inquiries to understand the functionality and design requirements of the website. This type of testing, and design reiteration, should continue throughout the development process.

Direct observation includes:

• Knowing your audience
• Knowing the web medium
• User feedback early and throughout the development cycle

• Direct observation of users both in their workplace and in a testing/observation environment.

Include usability engineering as early as possible, from the moment you know that a project needs to be developed or revised.

• Evaluate existing or similar websites - Learn from earlier/existing design success and failures.

• Conduct user field studies and contextual inquiry - Understand users' work flows, tasks, profiles, environments, and how much they vary.

• Examine support enquiries and feedback – Requests for information or general comments are feedback that can reveal past issues and problems.

• Participatory methods - Understand users' tasks and generate design directions through collaboration with developers, users, and usability engineers.

• Professional interface design - A key to producing usable products is to have a professional interface designer work on the project.

• Interative usability tests - Multiple usability tests should be performed on the prototypes and development builds.

• Worldwide usability tests – Ask colleagues overseas to test and provide feedback.

Usability Activities in the Project Workflow

• Review previous usability reports.
• Review existing data on usability problems from records (bug system, support calls) and feedback.
• Perform field studies and contextual inquiries.
• Create user profiles.

• Identify any user interface design standards or guidelines.
• Usability test previous version.
• Perform user surveys.
• Develop user profiles.
• Perform field studies.
• Perform comparative usability tests.
• Perform participatory methods.
• Perform task analysis.
• Define usability goals.
• Create a user model.
• Write usability requirements.

• Designer creates designs
• Prototype interface
• Usability inspection
• Multiple rounds of usability testing
• Redesign
• International usability test
• Global use review
• Standards inspection
• Error message review
• Design review

• Iterative usability tests
• Redesign

• Field observation
• Measure if usability goals and requirements are met

• Observe real behaviour. Watch people do what they really do. Watch them perform their day to day tasks. Analyse what tasks are they really doing. (e.g. When someone uses a search engine, they are not really searching; they are problem solving.)
• Make the user feel comfortable and natural.
• Use a representative set of users (representative of your intended audience). Watch them resolving real problems and hypothetical problems.
• Understand a users’ performance, not their preference.

• Conduct user testing on sites other than your own.

Jakob Neilsen’s web site

Sun Microsystems Usability