Changes: Usability

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Usability is a term used to denote the ease with which people can employ a particular tool or other human-made object in order to achieve a particular goal. Usability can also refer to the methods of measuring usability and the study of the principles behind an object's perceived efficiency or elegance.

In human-computer interaction and computer science, usability usually refers to the elegance and clarity with which the interaction with a computer program or a web site is designed. The term is also used often in the context of products like consumer electronics, or in the areas of communication, and knowledge transfer objects (such as a cookbook, online help files etc). It can also refer to the efficient design of a mechanical objects such as a door handle or a hammer.

Introduction

The primary notion of usability is that an object designed with the users' psychology and physiology in mind are, for example:

More efficient to use—it takes less time to accomplish a particular task
Easier to learn—operation can be learned by observing the object
More satisfying to use

Complex computer systems are finding their way into everyday life, and at the same time the market is becoming saturated with competing brands. This has led to usability becoming more popular and widely recognised in recent years as companies see the benefits of researching and developing their products with user-oriented instead of technology-oriented methods. By understanding and researching the interaction between product and user, the usability expert can also provide insight that is unattainable by traditional company-oriented market research. For example, after observing and interviewing users, the usability expert may identify needed functionality or design flaws that were not anticipated.

In the user-centered design paradigm, the product is designed with its intended users in mind at all times. In the user-driven or participatory design paradigm, some of the users become actual or de facto members of the design team.

The term user friendly is often used as a synonym for usable, though it may also refer to accessibility. The use of terms user friendly and user friendliness should be avoided, as there are no widely accepted definitions for them, and they are thus often used without much substance.

There is no consensus about the relation of the terms ergonomics (or human factors) and usability. Some think of usability as the software specialization of the larger topic of ergonomics. Others view these topics as tangential, with ergonomics focusing on physiological matters (e.g., turning a door handle) and usability focusing on psychological matters (e.g., recognising that this door can be opened by turning that handle).

Defining usability

It has been suggested that [[::Usability Requirements|Usability Requirements]] be merged into this article or section. (Discuss)

Usability is often associated with the functionalities of the product (cf. ISO definition, below), in addition to being solely a characteristic of the user interface (cf. framework of system acceptability, also below, which separates usefulness into utility and usability). For example, an automobile lacking a reverse gear could be considered unusable according to the former view, and lacking in utility according to the latter view.

It is important to distinguish between usability testing and usability engineering. Usability testing is the measurement of ease of use of a product or piece of software. In contrast, usability engineering (UE) is the research and design process that ensures a product with good usability.

ISO standard

The document ISO 9126 (1991) Software Engineering Product Quality, issued by the International Organization for Standardization, defines usability as:

A set of attributes that bear on the effort needed for use, and on the individual assessment of such use, by a stated or implied set of users.

The document ISO 9241-11 (1998) Guidance on Usability, also issued by the International Organization for Standardization, defines usability as:

The extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use.

Jakob Nielsen's framework of system acceptability

Usability consultant Jakob Nielsen and computer science professor Ben Shneiderman have written (separately) about a framework of system acceptability, where usability is a part of "usefulness" and is composed of:

Learnability (e.g. intuitive navigation)
Efficiency of use
Memorability
Few and noncatastrophic errors
Subjective satisfaction

Usability considerations

Template:Wikify-date Usability includes considerations such as:

Who are the users, what do they know, and what can they learn?
What do users want or need to do?
What is the general background of the users?
What is the context in which the user is working?
What has to be left to the machine? What to the user?

Answers to these can be obtained by conducting user and task analysis at the start of the project.

Other considerations include:

Can users easily accomplish their intended tasks? For example, can users accomplish intended tasks at their intended speed?
How much training do users need?
What documentation or other supporting materials are available to help the user? Can users find the solutions they seek in these materials?
What and how many errors do users make when interacting with the product?
Can the user recover from errors? What do users have to do to recover from errors? Does the product help users recover from errors? For example, does software present comprehensible, informative, non-threatening error messages?
Are there provisions for meeting the special needs of users with disabilities? (accessibility)

Examples of ways to find answers to these and other questions are: user-focused requirements analysis, building user profiles, and usability testing.

Usability is now recognized as an important software quality attribute, earning its place among more traditional attributes such as performance and robustness. Indeed, various academic programs focus on usability. [1] Also several usability consultancy companies have emerged, and traditional consultancy and design firms are offering similar services.

References

Norman, Donald A. (2002). The Design of Everyday Things, Basic Books. ISBN 0-465-06710-7.
Jakob Nielsen (1994), Usability Engineering, Morgan Kaufmann Publishers, ISBN 0-12-518406-9
Ben Shneiderman: Software Psychology, 1980
Andreas Holzinger: Usability Engineering for Software Developers, Communications of the ACM (ISSN: 0001-0782), Vol. 48, Issue 1 (January 2005), 71-74

External links

See also external links for Web usability.

Professional Associations

Usability Professionals' Association — an organization for people practicing and promoting usability
ACM SIGCHI — the ACM's Special Interest Group on Computer-Human Interaction
STC Usability & User Experience Community — Usability and User Experience Community of the Society for Technical Communication
Human Factors and Ergonomics Society (HFES)

Research & Peer-Reviewed Journals

Design Critiques

Bad Human Factors Designs — examples of bad design
User Centered — critiques on design, usability discussion

References

Interaction-Design.org — an open-content encyclopedia about usability

Lists of Links

Human Factors International Suggested Links
EServer TC Library: Usability
Usability Views — collectes links to articles and news related to usability

Fun

User Friendly — User Friendly webcomics

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This page uses Creative Commons Licensed content from Wikipedia (view authors).

@@ Line 1: / Line 1: @@
-{{SpecsPsy}
+{{SpecsPsy}}
-'''Usability''' is a term used to denote the ease with which people can employ a particular [[tool]] or other human-made object in order to achieve a particular goal. Usability can also refer to the methods of measuring usability and the study of the principles behind an object's perceived efficiency or elegance.
+'''Usability''' is a term used to denote the ease with which people can employ a particular tool or other human-made object in order to achieve a particular goal. Usability can also refer to the methods of measuring usability and the study of the principles behind an object's perceived efficiency or elegance.
-In [[human-computer interaction]] and [[computer science]], usability usually refers to the elegance and clarity with which the interaction with a [[computer program]] or a [[web site]] is designed. The term is also used often in the context of products like [[consumer electronics]], or in the areas of [[communication]], and [[knowledge transfer]] objects (such as a [[cookbook]], a [[document]] or [[online help]]).  It can also refer to the efficient design of a [[machine|mechanical]] objects such as a door handle or a [[hammer]].
+In [[human-computer interaction]] and [[computer science]], usability usually refers to the elegance and clarity with which the interaction with a computer program or a web site is designed. The term is also used often in the context of products like consumer electronics, or in the areas of [[communication]], and [[knowledge transfer]] objects (such as a cookbook, online help files etc).  It can also refer to the efficient design of a mechanical objects such as a door handle or a hammer.
 == Introduction ==
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 * More [[satisfaction|satisfying]] to use
-Complex computer systems are finding their way into everyday life, and at the same time the market is becoming saturated with competing [[brand]]s. This has led to usability becoming more popular and widely recognised in recent years as companies see the benefits of researching and developing their products with user-oriented instead of [[technology]]-oriented methods. By understanding and researching the [[interaction]] between product and user, the '''usability expert''' can also provide insight that is unattainable by traditional company-oriented [[market research]]. For example, after observing and interviewing users, the usability expert may identify needed functionality or design flaws that were not anticipated.
+Complex computer systems are finding their way into everyday life, and at the same time the market is becoming saturated with competing brands. This has led to usability becoming more popular and widely recognised in recent years as companies see the benefits of researching and developing their products with user-oriented instead of [[technology]]-oriented methods. By understanding and researching the [[interaction]] between product and user, the '''usability expert''' can also provide insight that is unattainable by traditional company-oriented [[market research]]. For example, after observing and interviewing users, the usability expert may identify needed functionality or design flaws that were not anticipated.
-In the '''[[user-centered design|user-centered]]''' design [[paradigm]], the product is designed with its intended users in mind at all times. In the '''user-driven''' or ''participatory'' design paradigm, some of the users become actual or [[de facto]] members of the design team.
+In the '''[[user-centered design|user-centered]]''' design paradigm, the product is designed with its intended users in mind at all times. In the '''user-driven''' or ''participatory'' design paradigm, some of the users become actual or de facto members of the design team.
 The term '''user friendly''' is often used as a synonym for ''usable'', though it may also refer to [[accessibility]]. The use of terms ''user friendly'' and ''user friendliness'' should be avoided, as there are no widely accepted definitions for them, and they are thus often used without much substance.