Web Usability

Usability is not exclusive to the web. It refers to the relationship between tools and their users, so it is applicable to practically any field. Usability is usually defined as the measure of the ease with which particular people can employ a particular tool.

Within the web development process, usability is the set of techniques used during the design of the web site in order to improve the ease of use to everybody, including those with disabilities. Web usability is based on two main principles:

• Visitors only see what they need: Internet users don’t read in detail, they skim the web trying to find what they are really interested in. If they can’t find what they are looking for, they will leave your site.
• Visitors are impatient: They want to access the relevant information as soon as possible. If they can’t find what they are looking for quickly, they will leave your site.

Accessibility vs Usability

Web accessibility and usability both improve satisfaction, effectiveness, and efficiency of users. But while accessibility is aimed at making the web site open to a wider user population, usability is aimed at making the target population of the web site happier, more efficient, more effective.
Accessibility covers technical issues; usability is experiential. It is about the user’s experience when accessing a web site. Usability is very much like quality: you typically notice it only when it is missing.

Usability Factors

Web usability is about making your web site in such a way that your site users can find what they're looking for quickly and efficiently. A usable web site can reap huge benefits on to your website and your business:

"A web usability redesign can increase the sales/conversion rate by 100%" (source: Jakob Nielson2)

Web usability is not just about making sure everything on the site works, but also how quickly and easily visitors are able to make use of the site. Web usability covers download time, page layout, graphics, animation, navigation, information architecture, search, etc... it can only be measured by the end user’s experience and satisfaction. Here are some examples:

• The web site should be easy to find by search engines.
  
• The web site should be quick to download.
  
• The user should easily find the information he/she is looking for.
  
• The services offered should be easy to access and understand.
  
• The web page layout and design should be consistent throughout the site.
  
• The site should has a logical structure and efficient navigation.
  
• Explanations should be provided on how the site is organized.
  
• The user should be able to interact with the site and provide feedback.
  
• The site should offer some search features.