According to Wikipedia, “Usability testing is a technique used in user-centered interaction design to evaluate a product by testing it on users. This can be seen as an irreplacable usability practice, since it gives direct input on how real users use the system…Usability testing focuses on measuring a human-made product’s capacity to meet its intended purpose. Examples of products that commonly benefit from usability testing are websites or web applications, computer interfaces, documents, and devices. Usability testing measures the usability, or ease of use, of a specific object or set of objects…”
A multi-task usability test was conducted on one of an organization’s web applications with internal users, a mix of individuals from customer support and training. Then, the same usability test was given to a group of expert external users. One of the test objectives was to determine if there was a significant gap in usability between internal and external users. The result was that there was no difference in the usability of the application between the internal and external users.