As web usability has increasingly become an important component of gauging the success of a website, it has become an important principle to take note of.

Usability generally refers to how easy it is for users to utilize a certain tool to achieve its purpose.

In the case of developing and the design of websites, it has become an important measuring tool to use to gauge the future success of a website.

In trying to improve or enhance the usability of a website, it is important for the webmasters to first know about the different elements that determine usability.

There are certain guidelines that web designers and web developers can follow to help them gauge the usability of the website.

According to Jakob Nielsen, a foremost expert on usability, there are five elements that determine the usability of a website or any other tool or man-made object.

Efficiency

This element indicates the speed on which experienced users may be able to accomplish certain tasks once they have learned about the different functions or features provided for in the website.

This is important for websites that target heavy users and web design and structure should work upon the efficiency with such knowledgeable users in mind.

Learnability

This is a measure of how fast users may be able to accomplish certain processes and tasks provided as functions on the website. Websites that score high on learnability can also be generally considered as a site with high usability.

Emphasis on learnability when gauging a website's usability may depend on the specific audience that a website tries to target.

If the website focuses on less experienced online users, learnability may be emphasized when determining usability.

For websites that focus on reaching out to more savvy users, efficiency may be emphasized more to gauge the usability of a website instead of learnability.

Memorability

This element is a measure of how easy it is for previous online users to remember how to use a website when they get back to it.

This is important for e-commerce websites that don't target frequent users often but may want their visitors to quickly recall the processes that they have to go through to make purchases on the site.

Learnability is closely linked to the element of memorability. The higher the site's learnability range, the higher also the site scores on the memorability scale.

Errors

This element can determine a website's usability in the sense that if there are fewer errors, the less difficulty users have to go through in using the site.

This element can also determine usability in cases where users themselves commit the errors but is able to recover quickly without outside assistance.

A website should be evaluated for possible errors, both from the design of the website itself as well as on the many instances that a user may possibly commit one.

Satisfaction

This element is a measure of the level of user experience upon using or visiting a website. How a user leaves a website feeling satisfied or enjoying the experience can be an important characteristic of its usability.

This can be applied for the design of entertainment-related sites such as those offering online games or dating services but may also be generally essential in different degrees with other types of websites.