Hi, need to submit a 500 words paper on the topic Software Usability. What do you believe are the appropriate criteria for assessing usability? Who should make such judgments? How should disagreements about usability be resolved? To develop an appropriate criterion to assess usability it is of critical importance that one understands what the concept of usability entails. Usability is a measure of the quality of a user interface. It measures how simple and easy a user interface is to use. How we judge usability is dependant on five quality components as defined by Jakob Neilson. These being learnability, efficiency, memorability, errors and satisfaction. Building on these concepts basic criteria for the evaluation of usability can be formed. A critical point in this assessment is to know that it is central on the reactions and the actions of the users for who the interface is designed. That being said, the first criteria would be the ease with which a first time user can perform basic tasks on the site. This would judge the complexity of the site design, how user friendly it is and is pivotal to the learnability aspect. Second, we look at the speed with which the regular user’s, who are more familiar with the design, perform tasks. This forms a building block in the efficiency component of usability by reflecting how successful the basic interface design is at facilitating usability. Next we assess usability by looking at the rate of recall of user’s who return to the design after a prolonged period. How easily these users’s can go back to efficiently using the interface to perform tasks and the number of errors they make while they’re at it will be used to evaluate the memorability and errors aspect of usability. Another key determinant of usability is the overall satisfaction level of the user’s. If their experience with the usage of the design is positive and pleasant it will denote a higher level of usability. According to Jean Scholtz’s ‘Usability evaluation’, Usability engineers and usability experts undertake the task of evaluating usability. Since they are responsible for the design of the interface and deciding what attribute should be central to the development of the interface’s design. For example, if the application is time critical usability engineers will concentrate on the usability quality component of efficiency whereas memorability will be given more priority if the software is used infrequently. Furthermore to facilitate judgments to assess usability some commonly used evaluation methods are used, by usability experts, in software design today. These methods are also responsible for providing guidance on how to resolve various usability disputes. The first of these measures is Card sorting, this is a useful tool which helps to determine how information that appears on a website is categorized by users. Another measure is the use of Charrettes, this is a generative exercise which aims at coming up with design solutions by taking into account the viewpoints of various stakeholders of the project. Cognitive walkthroughs are also used by usability experts to evaluate the usability for a website by the division of the task procedures into smaller steps that the expert analyzes. Contextual task analysis uses basic observation of the user to come up with tools that will facilitate the tasks performed by the user. Facilitated brain storming and the use of focus groups are also two measure’s to judge usability. Heuristic evaluation, Surveys, One-on-one interviews are also some commonly used measures. And finally Quality assurance testing and Usability testing are two very important measures to access quality and the experience that user’s have on your website. (Usability methods, web) Work Cited Jakon Neilson. Usability 101. Web. Retrieved, January 30, 2011, from: . Jean Scholtz. Usability Evaluation. National Institute of Standards and Technology. Web. Retrieved, January 30, 2011, from: . ‘Usability Methods.’ Usability first. Web. Retrieved January 30, 2011, from: .