Information Technology: Decomposition Aspects of Usability

Usability of software programs interfaces, websites as well as the ease with the ability of a user to accomplish the task using a web-based or software application. A site or program with a high level of usability allows users to quickly complete the tasks, learn quickly and provide a satisfying experience. Numerous organizations like ISO/IEC 9126, ISO 9241 as well as IEEE Std.610.12 have set guidelines for usability. software developers and web designers are required to adhere to the standards set by these organisations. This paper analyzes the decomposition elements of usability.

The section provides an overview of usability in accordance with ISO 9126 and ISO 9124. A breakdown of attributes is included.

In accordance with ISO/IEC 9126, the quality of software is classified by six categories, which are functional, usability, portability Maintainability, Efficiency and Reliability. It is built on the viewpoint of the user and results an aspect of quality. There are four elements of ISO/ IEC 9126. According to the ISO/9126 standard, usability can be defined as "A set of characteristics which are related to the amount of effort required to usage and the personal assessment of that usage by a specified or implied group of people". The components of Usability are comprehendability, learnability and usability, operability and attractiveness and compliance (Abran 2002).

ISO 9241-11 provides the guidelines and requirements for hardware, software ergonomics, ergonomics, and the environment for users. All of the elements contribute to defining usability. There are 17 components in this standard: parts 1 to 2 addresses the general requirements. Parts 3-9 address the physical requirements, while part 9 covers the environmental requirements, and parts 10-17 cover the requirements for software. The standard defines usability by saying: "Software is usable when it lets the user perform his job with efficiency with efficiency and satisfaction within the specific context of use". The principles of dialogue are Usability standards and measures such as the presentation of data, direction dialogs for command, menus direct manipulation dialogues, and forms filling dialogues (Abran 2002).

The ISO/IEC-9126-2001 standard employs an approach that is oriented towards the product and the usability of the software was not based upon the performance of the program, but rather how many bugs it had, whether it crashed, etc. Usability was primarily based on interface elements like hyperlinks, radio buttons safe colors for the web drop-down boxes as well as text entry boxes and so on . The importance was placed on how easy users found it to use the software.

There was not much attention paid to how well the program actually worked, or the speed at which tables of data were constructed or nesting tables, and the like. The attributes of software means that its usability will depend on the kind that user is using the software, as well as on the job to be completed as well as the environment that the user was working in. In a way that is primarily product-oriented the quality of software is not considered. However, ISOIEC: 9126-2001 IEC 9126-2001 indicates that the ability of the site, application or software must be learned to be understood, accepted and accepted by the user when it is utilized under a set specific requirements (Abran 2002).

Within ISO 9241, the part 11 sections explain the significance and the process and steps that should be considered when defining usability as a measurement of the user's satisfaction as well as their efficiency. The standard incorporates three quality indicators to assess the usability of an application. They are: effectiveness, in which it is established how the user will accomplish the task they desired to accomplish when they decide to use the software; efficiency which is the amount of resources needed been consumed in order to complete the tasks , and satisfaction when users be satisfied with the system.

It is important to note that the ISO 9241 standard has set guidelines that can be used to assess the usability of a software according to the context of the software but it is essential to realize that the conclusions generated from the test depend on the nature of the application and the intended goals in the evaluation. The understanding of the contextual and characteristics of the usage can lead to useful products and items. Context features include users, tasks and the environment. These are crucial when trying to establish the usability an attribute for the item.

The notion of usability is contingent on the level of skill of the user. A product intended for skilled and experienced users might not make sense to a beginner or inexperienced user. Features like the users interface on a product can be improved by using web-safe colors that aren't visually jarring and avoiding the use of animated gifs which could cause heart attacks. This can be done through the proper usage of skin and background colours using menus, fonts, and font colours that are easy to read. Certain applications will warning when a mouseover is completed and the pop-up text provides information that cannot be displayed on buttons (Abran 2002).

ISO 9241-11 has some advantages over ISO/IEC 9226-2001. it is: ISO 9241 focuses on aspects of usability. The environment of components' use is considered when making a decision on the specifications, design and usability evaluation. The satisfaction of the user as well as the quality of performance are able to provide direct measures of the level of usability within the specific situation. The measure of satisfaction and performance the user is a basis which can be used to make a analysis of other elements in design as well as usability within the specific situation. A large portion of usability is determined by the standard that is in line with the standards in ISO 9001 (Abran, 2002).

ISO 9241-11-98 is not without its disadvantages over ISO/IEC 92126-2001. it is because usability is considered from the perspective of the procedure to be utilized, and therefore it's a process of viewpoint in contrast to ISO 9126 is a product view. ISO 92411 does not consider matters like learnability and is required by various standards. The standard does not examine the security aspects which is thought to be crucial when software needs being evaluated for usability (Abran 2002).

The below questionnaire can be used to determine the usability of software. This SUMI questionnaire is built on the inventory of usability in software and is a testing method which is used to assess the quality of software and its usability. There are several subscales within the software and they include global, efficiency Affect, Helpfulness Control, and Learnability. An application that is widely used is a tool to determine its usefulness and its users can be asked to complete the questionnaire by grading points between 1 and five on the scale. One score means completely disagree, and 5 means completely in agreement. (SUMI, 2007).

Bevan (2001) Has suggested a new model which could provide a more accurate representation of usability. Based on this model, Usability would have the following categories of Efficiency, Effectiveness Satisfaction, Security , and Learnability. These decompositions could contain a range of sub attributes which would be able to fill the gaps in both the ISO and ISO models. Effectiveness would include measures such as the percentage of tasks completed as well as the ratio of failure handling and the percentage of tasks completed per hour.

Efficiency will have quantifiable aspects like numbers of both good and bad attributes that users recall, the time it takes to complete a task, the time it takes to fix errors, errors percentage and documentation of help usage frequency, revisions number for failed command, and the number of commands available that have not been used. The measure of satisfaction would include proportion of users with positive and negative comments. Security would be a measure of simple human readiness, ability to cancel executions easily by users, and easy input and output, and instructional readiness. Learnability is an indicator of the time it takes to search to find information.

The paper has investigated the standards of ISO 9241-11 and ISO 9126 and examined various sub-aspects of each as well as the definition of usability according to these two standard. The paper also analyzed the strengths and weaknesses of both standards and included a questionnaire which can be used to evaluate the usability of a website. Future suggestions based on these standard have been suggested.