What Is Usability?
Posted in General Business, Project Managment on November 10th, 2010 by RachaelNeilson (2003) describes usability as a “quality attribute” that measures the user-friendliness of interfaces. Usability can be split into the following criteria (Rogers, 2007):
• Effectiveness
• Efficiency
• Safety
• Utility
• Learnability
• Memorability
If a product satisfies the above usability goals, it is said to be usable. Usability can be split into many different perspectives, three of which are discussed below.
Cognitive Usability
Cognitive usability is the idea that information can be understood, rather than just perceived (Kato, 2006). For example, a website containing information on bus timetables may be easily accessible, however if the timetable presented on the website is hard to understand or interpret, it is not cognitively usable. To ensure cognitive usability, designers must strive for efficiency and learnability; which can be achieved by using clear, concise language in conjunction with simple, uncluttered interfaces.
Mobile Usability
The term “mobile usability” refers to the usability of small, mobile devices (Costa, 2007). Mobile devices, such as PDA’s, blackberries and mobile phones, are very small, and so the number of buttons and size of the screen are limited. There are many trade-offs between the “quality” attributes when designing mobile devices (Costa, 2007). For example, a standard mobile phone has the alphabet compacted into 9 buttons. This allows for larger, more physically usable buttons than a phone 26 buttons for the alphabet; however it can mean some tasks are less efficient to do (such as typing a text message). Thus when designing for mobile devices, developers often find a balance between physical usability and efficiency.
Web Usability
Web usability is the usability associated with a website. Usability of a website is particularly important because if it is difficult to use or hard to understand, the user will simply leave (Nielsen, 2003). Good web usability means that a website clearly states its subject matter, as well as being easy to navigate, read and understand. At Kintek, we focus mainly on learnability and effectiveness and efficiency to make your website stand out from the rest.
References
Costa, C. J., Silva, J.P.N. & Aparício, M (2007). Evaluating Web Usability Using Small Display Devices. Paper presented at the 25th Annual ACM International Conference on Design of Communication.
Kato, T., Hori, M. (2006). “Beyond Perceivability”: Critical Requirements for Universal Design of Information. Paper presented at the 8th international ACM SIGACCESS conference on Computers and Accessibility.
Nielson, J. (2003). Usability 101: Introduction to Usability. Retrieved 10 March, 2008, from http://www.useit.com/alertbox/20030825.html.
Rogers, Y., Sharp, H. & Preece, J. (2007). Interaction design: Beyond human-computer interaction (2nd ed.). New York: Wiley.
