Usability means the assessment of quality of interaction between human and computer systems. This concept takes into account design engineering, philosophy, cognitive psychology and ergonomics coverage.
Meaning of Usability :
The idea behind usability is to evaluate the effectiveness of user and system interaction. The parameter for measurement is the user's behaviour in terms of comfort or ease of handling the system, the time consumed to perform a task in a certain kind of environment (virtual and physical).
Accessibility establishes a relation between the concept of usability and the extent of problem.
In modern day, we are flooded with applications, web or mobile, which are quite complex. The usability of such applications can certainly determine the success or failure. The focus has shifted to usability by the industries and they are trying to adopt various usability evaluation methods.
When accessing a web application a user may come across various functionalities within it. A user has endless options to manage and access the components, like navigating to various sites, managing tabs etc. Every browser has a well defined structure which depicts a clear understanding of how to access or manage elements. Hence it won't be incorrect to say that accessibility of web applications depends on its usability. Usability is important in determining the quality of web applications.
Now let's have a detailed discussion on the various usability evaluation methods :
Think aloud protocol -This technique can be applied to design, code and testing phases of an application. In this, the members involved in the testing process give opinion on the application while the execution is still on. As the name suggests, this protocol involves free thinking. Participants are free to state whatever thoughts flash across their minds. This protocol largely emphasises on the thought process of a person, and aims to view the product from that perspective instead of looking at it as just a product.
Remote Usability Testing -In this technique, there is involvement of the users. It is a measure to evaluate how the system is being used in a real world scenario. So it simply tests usability, that is, the ease or simplicity with which a user is able to access the system. The term remote is prefixed with usability testing when the prospective users, developers, and usability evaluators are located at different geographical locations and time zones.
Remote testing can be synchronous and asynchronous. In synchronous testing, the evaluator and the user interact directly with one another, in asynchronous the evaluator and the user works separately.
Focus Groups -It aims for a open end discussion wherein a group of people sit together and exchange their ideas, opinions, beliefs towards a product, service, concept, advertisement, idea etc. During the process, the researcher either notes down the reviews or the major points.
Interviews - This is a direct one to one conversation either face to face or through video conferencing. It is again a form of open ended discussion where there is free exchange of opinions and ideas. The evaluator may act as the interviewer and the end user as interviewee. The interviewer records the answers of the respondent. There are various formats for conducting interview. The recording of information can be done either in writing or in video or audio format.
Cognitive Walkthrough -This is the process of analysing the task first, which specifies a sequence of actions that needs to be done at the user end to accomplish a task, and how the system responds to those actions. Then the designers and developers 'walk through' these steps to finally arrive at a conclusion. If any sort of erroneous issues are reported, they are addressed later on.
Pluralistic Walkthough -It is an user centric walkthrough, an usability inspection method that is used to identify the usability issues in a software. It involves a group of users, developers and usability professionals to walk through each task scenario. It can be used in early design phases. This type of usability test helps to sensitise the developers towards their end customers.
Usability testing is an essential activity in the process of developing a product that is simple and robust and the end user benefits from such a system.