Interaction Design Patterns

 

An interaction design (ID) pattern is a general repeatable solution to a commonly-occurring usability problem in interface design or interaction design. An ID pattern usually consists of the following elements:

  • Problem: Problems are related to the usage of the system and are relevant to the user or any other stakeholder that is interested in usability.
  • Use when: a situation (in terms of the tasks, the users and the context of use) giving rise to a usability problem. This section extends the plain problem-solutions dichotomy by describing situations in which the problems occur.
  • Principle: a pattern is usually based on one or more ergonomic principles such as user guidance, or consistency, or error management.
  • Solution: a proven solution to the problem. A solution describes only the core of the problem, and the designer has the freedom to implement it in many ways. Other patterns may be needed to solve sub problems.
  • Why: How and why the pattern actually works, including an analysis of how it may affect certain attributes of usability. The rationale (why) should provide a reasonable argument for the specified impact on usability when the pattern is applied. The why should describe which usability aspects should have been improved or which other aspects might suffer.
  • Examples: Each example shows how the pattern has been successfully applied in a real life system. This is often accompanied by a screenshot and a short description.
  • Implementation: Some patterns provide implementation details.

As numerous people have worked on the patterns in Human Computer Interaction in recent years, the concept of an ID patterns is known under different names; e.g. interaction patterns, user interface (UI) patterns, usability patterns, web design patterns, and workflow patterns. These patterns share a lot of similarities and basically all provide solutions to usability problems in interaction and interface design. Some patterns are known under different names (or even the same name) in different pattern collections.

History of interaction design patterns

Patterns originated as an architectural concept by Christopher Alexander (1977). Patterns and pattern languages for describing patterns are ways to describe best practices, explain good designs, and capture experience in a way that it is possible for others to reuse this experience. In addition to the patterns Alexander defined a set of rules e.g. a pattern language in which patterns could be meaningfully combined. Design pattern (computer science) are extensively used by software engineers for the actual design process as well as for communicating a design to others. Software patterns first became popular with the object-oriented Design Patterns: Elements of Reusable Object-Oriented Software book. Since then a pattern community has emerged that specifies patterns for all sorts of problem domains: architectural styles, object oriented frameworks, domain models of businesses and interaction design. The first substantial set of interaction design patterns was the Common Ground pattern collection, developed by Jenifer Tidwell. Many other collections and languages followed, such as Martijn van Welie's Interaction Design Patterns. Several books have recently been published about Web and UI design patterns, including:

  • A Pattern Approach to Interaction Design, by Jan Borchers (2001)
  • A Pattern Language for Web Usability, by Ian Graham (2003)
  • The Design of Sites: Patterns, Principles, and Processes for Crafting a Customer-Centered Web Experience, by Douglas K. van Duyne, James A. Landay, and Jason I. Hong (2002)
  • Designing Interfaces: Patterns for Effective Interaction Design, by Jenifer Tidwell (2005)

Example interaction design pattern: Multi-level Undo

 



Undo in Microsoft Word using a visualization of the command queue

Author 

Martijn van Welie http://www.welie.com/patterns/gui/undo.html

Problem 

Users do actions they later want reverse because they realized they made a mistake or because they changed their mind.

Use when

You are designing a desktop or web-based application where users can manage information or create new artifacts. Typically, such systems include editors, financial systems, graphical drawing packages, or development environments. Such systems deal mostly with their own data and produce only few non-reversible side-effects, like sending of an email within an email application. Undo is not suitable for systems where the majority of actions is not reversible, for example, workflow management systems or transaction systems in general.

Both novice and expert users may want to reverse their actions, either because of mistakes or changes in intention. Expert users may want to use the history of their actions for more specific manipulation of the data in the application. For example, in a graphical modeling application, users may want to undo work on some specific object while keeping later work done on other objects.

Principle 

Error Management (Safety) (Norman, 1988)

Solution 

Maintain a list of user actions and allow users to reverse selected actions.

Each 'action' the user does is recorded and added to a list. This list then becomes the 'history of user actions' and users can reverse actions from the last done action to the first one recorded. This is also called a Linear Multi-level Undo.

Interacting with the history

There are two variations on how to show the history of actions to the users. First there is the standard 'office-like' way where the 'Edit' menu contains both 'Undo' and 'Redo' functions with their keyboard shortcuts. Often there is also a widget in the toolbar that can show the last items in the history. By dragging the selection in the list, actions can be undone. A second variant is to work with primarily with the history list itself and moving a slider or scrollbar to move back in history and undo actions. Photoshop uses such a variant.

Displaying actions

Actions in the history are usually displayed using a text label such as 'Create circle', 'Typing',' New contact'. Such labels only name the function and not the object the functions work on. In some applications it may be better to include the object and the parameters as well, for example 'Change-color Circle12 to Red'.

Granularity of actions

When designing Undo it is important to determine the desired granularity of actions. For example, it is usually not desired to record each key press in a text editor as an action. Instead, typing a word is used as a unit of action. Designers need to determine what unit of action is appropriate in the application.

Non-reversible actions

Although most actions in the application may be reversible, it is very likely that some actions will not be reversible. For example, printing, saving, doing a payment, or downloading an object. For actions that are non-reversible and 'negative' of nature (like paying or destroying something), need to show the user a Warning Message and not add the action to the history.

Selective undo

In some cases, it can be meaningful to allow single actions from the history to be deleted. This is the case when a certain 'episode' of work must be deleted or undone while keeping work that has been done later on. Selective undo is conceptually much more difficult than linear undo since there is a notion of 'dependency between actions' that determines the consequences of undoing a particular action. For example, if a 'create circle' action is undone at some point in the history, subsequent actions in the history working on that object loose their meaning and must be deleted. There are many semantic issues with selective undo, see Berlage (1994) for more information on selective undo.

Object-based Undo

Object-based Undo can sometimes be considered as an alternative to Selective Undo. With Object-based Undo, each object has its own action history. Upon selecting the object, the users can undo actions done on the object. Naturally, this requires the application to have a clear concept of an 'object' and is therefore not applicable for bitmap editors. See Zhou and Imamiya (1997) for more on Object-based Undo.

Multi-user undo

If the application is a multi-user application and uses undo, the application must distinguish between local actions and global actions. That leads to multiple histories and requires special semantics for what happens when undoing actions. See Abowd and Dix (1992) and Sun (2000) and Ressel and Gunzenhouser (1999) for more on multi-user undo issues.

Why 

Offering the possibility to always undo actions gives users a comforting feeling. It helps the users feel that they are in control of the interaction rather than the other way around. They can explore, make mistakes and easily go some steps back, which facilitates learning the application's functionality. It also often eliminates the need for annoying warning messages since most actions will not be permanent

Examples 


As in all MS Office applications, in Word 2000 the users can see the history of their actions and undo one or more of them. The actions are briefly described and the users can select a range of actions to be undone. After selecting undo, users can even redo the actions.


In Photoshop a selective undo is also possible. By moving the slider, users can do the normal multi-level undo but they can also drag an action into the trashcan and thereby do a selective undo. Operations that depended on that action are automatically deleted as well of they are not relevant anymore.

Implementation 

Most implementations of multi-level undo are based on the Command (Gamma et al 1995) pattern. When using the Command pattern, most functionality is encapsulated in Command objects rather than in other controlling classes. The idea is to have a base class that defines a method to "do" a command, and another method to "undo" a command. Then, for each command, you derive from the command base class and fill in the code for the do and undo methods. The "do" method is expected to store any information needed to "undo" the command. For example, the command to delete an item would remember the content of the item being deleted.

 

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References

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Abowd, Gregory D. and Dix, Alan J. (1992): Giving Undo Attention. In Interacting with Computers, 4 (3) pp. 317-342.

The problems associated with the provision of an undo support facility in the context of a synchronous shared or group editor are investigated. Previous work on the development of formal models of 'undo' has been restricted to single user systems and has focused on the functionality of undo, as opposed to discussing the support that users require from any error recovery facility. Motivated by new issues that arise in the context of computer supported co-operative work, the authors aim to integrate formal modelling of undo with an analysis of how users understand undo facilities. Together, these combined perspectives of the system and user lead to concrete design advice for implementing an undo facility. The special issues that arise in the context of shared undo also shed light on the emphasis that should be placed on single user undo. In particular, the authors regard undo not as a system command to be implemented, but as a user intention to be supported by the system.

© All rights reserved Abowd and Dix and/or Elsevier Science

Alexander, Christopher, Ishikawa, Sara and Silverstein, Murray (1977): A Pattern Language. Oxford University Press

Berlage, Thomas (1994): A Selective Undo Mechanism for Graphical User Interfaces Based on Command Objects. In ACM Transactions on Computer-Human Interaction, 1 (3) pp. 269-294. Available online

It is important to provide a recovery operation for applications with a graphical user interface. A restricted linear undo mechanism can conveniently be implemented using object-oriented techniques. Although linear undo provides an arbitrarily long history, it is not possible to undo isolated commands from the history without undoing all following commands. Various undo models have been proposed to overcome this limitation, but they all ignore the problem that in graphical user interfaces a previous user action might not have a sensible interpretation in another state. Selective undo introduced here can undo isolated commands by copying them into the current state "if that is meaningful." Furthermore, the semantics of selective undo are argued to be more natural for the user, because the mechanism only looks at the command to undo and the current state and does not depend on the history in between. The user interface for selective undo can also be implemented generically. Such a generic implementation is able to provide a consistent recovery mechanism in arbitrary applications.

© All rights reserved Berlage and/or ACM Press

Borchers, Jan O. (2001): A Pattern Approach to Interaction Design. John Wiley and Sons

Gamma, Erich, Helm, Richard, Johnson, Ralph and Vlissides, John (1995): Design Patterns: Elements of reusable object-oriented software. Addison-Wesley Publishing

Graham, Ian (2003): A Pattern Language for Web Usability. Pearson Education

Norman, Donald A. (1988): The Design of Everyday Things. New York, Doubleday

Ressel, Matthias and Gunzenhauser, Rul (1999): Reducing the Problems of Group Undo. In: Proceedings of the International ACM SIGGROUP Conference on Supporting Group Work 1999 November 14-17, 1999, Phoenix, Arizona, USA. pp. 131-139. Available online

Providing undo functionality in groupware has been identified as an important, but difficult problem. Existing solutions show deficiencies like lacking generality, being too complex, being inefficient, or failing to yield acceptable results in common situations. In this paper we describe a new approach which reduces local group undo to a transformation-based method for combining the effects of concurrently issued user commands. Besides transformations we introduce mirror and folding operators in order to build a unique and consistent multidimensional model of the user interaction. In this way the problems of group undo mentioned above can be either overcome or at least reduced.

© All rights reserved Ressel and Gunzenhauser and/or ACM Press

Sun, Chengzheng (2000): Undo Any Operation at Any Time in Group Editors. In: Kellogg, Wendy A. and Whittaker, Steve (eds.) Proceedings of the 2000 ACM conference on Computer supported cooperative work 2000, Philadelphia, Pennsylvania, United States. pp. 191-200. Available online

The ability to undo operations is an indispensable feature of real-time group editors, but supporting group undo is a difficult problem. None of the existing solutions for group undo is able to support undoing any operation at any time with guaranteed success. In this paper, we contribute a novel group undo solution with such a capability. The basic idea is to interpret an undo command as a concurrent inverse operation by means of operational transformation, so that an operation is always undoable regardless of its undo context. By separating undo policy from undo mechanism, multiple undo modes, such as single-step undo, chronological undo, and selective undo, can be supported in the same collaborative editing session. In addition, solutions to known undo puzzles are also provided. A web-based group text editor using the proposed undo solution has been implemented and is accessible at: http://reduce.qpsf.edu.au.

© All rights reserved Sun and/or ACM Press

Tidwell, Jenifer (2005): Designing Interfaces: Patterns for Effective Interaction Design. O'Reilly and Associates

van Duyne, Douglas K., Landay, James A. and Hong, Jason I. (2002): The Design of Sites: Patterns, Principles, and Processes for Crafting a Customer-Centered Web Experience. Addison-Wesley Publishing

Zhou, Chunbo and Imamiya, Atsumi (1997): Object-based Linear Undo model, Proceedings of the Proceedings of the IFIP TC13 International Conference on Human-Computer Interaction. In: Howard, Steve, Hammond, Judith H. and Lindgaard, Gitte (eds.) Proceedings of INTERACT 97 - IFIP TC13 Sixth International Conference on Human-Computer Interaction July 14-18, 1997, Sydney, Australia. pp. 252-259.

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The Interaction-Design.org Addendum to the Creative Commmons licence is a placeholder for additions to the Creative Commons licence, which are deemed necessary to include in consideration of Danish law and the operation of this site and The Interaction-Design.org Foundation.

1. Attribution

Attribution must be clearly given, i.e. the author's name, the title and URL of this work/publication/web page must clearly appear. The attribution must be given in a manner appropriate to the medium in which it is given: For example, electronic copies must include a clickable URL, which does not use the nofollow attribute value.

2. Updates

The Interaction-Design.org Foundation reserves the unilateral right to update, modify, change and alter its Site Terms and Conditions as well as Copyright Terms at any time. All such updates, modifications, changes and alterations are binding on all users and browsers of Interaction-Design.org and will be posted here.

iii. Exceptions

Exceptions

In some cases, a page/work may include content, such as an image, that is not covered by the copyright terms (i.e. "The Interaction-Design.org Addendum to the Creative Commons licence" and the "Creative Commons Attribution-ShareAlike 3.0 Unported"). When this is the case, we clearly label the content. For images, we also include the copyright label inside the image file (i.e. the full-resolution version) in metadata types like EXIF, IPTC, and XMP. We only include and label content with the following copyright terms:

  1. CC-Att-SA:
        Creative Commons Attribution-ShareAlike 3.0 Unported
        Legal Code (full licence text): http://creativecommons.org/licenses/by-sa/3.0/
  2. CC-Att-SA-2:
        Creative Commons Attribution-ShareAlike 2.0 Unported
        Legal Code (full licence text): http://creativecommons.org/licenses/by-sa/2.0/
  3. CC-Att-SA-3:
        Creative Commons Attribution-ShareAlike 3.0 Unported
        Legal Code (full licence text): http://creativecommons.org/licenses/by-sa/3.0/
  4. CC-Att-SA-1:
        Creative Commons Attribution-ShareAlike 1.0 Unported
        Legal Code (full licence text): http://creativecommons.org/licenses/by-sa/1.0/
  5. CC-Att-ND:
        Creative Commons Attribution-NoDerivs 3.0 Unported
        Legal Code (full licence text): http://creativecommons.org/licenses/by-nd/3.0/
  6. CC-Att-ND-1:
        Creative Commons Attribution-NoDerivs 1.0 Unported
        Legal Code (full licence text): http://creativecommons.org/licenses/by-nd/1.0/
  7. CC-Att-ND-2:
        Creative Commons Attribution-NoDerivs 2.0 Unported
        Legal Code (full licence text): http://creativecommons.org/licenses/by-nd/2.0/
  8. CC-Att-ND-3:
        Creative Commons Attribution-NoDerivs 3.0 Unported
        Legal Code (full licence text): http://creativecommons.org/licenses/by-nd/3.0/
  9. CC-Att:
        Creative Commons Attribution 3.0 Unported
        Legal Code (full licence text): http://creativecommons.org/licenses/by/3.0/
  10. CC-Att-2:
        Creative Commons Attribution 2.0 Unported
        Legal Code (full licence text): http://creativecommons.org/licenses/by/2.0/
  11. CC-Att-3:
        Creative Commons Attribution 3.0 Unported
        Legal Code (full licence text): http://creativecommons.org/licenses/by/3.0/
  12. CC-Att-1:
        Creative Commons Attribution 1.0 Unported
        Legal Code (full licence text): http://creativecommons.org/licenses/by/1.0/
  13. AllRightsReserved:
        All Rights Reserved. Materials used with permission. Permission to use has been granted exclusively to The Interaction-Design.org Foundation and/or the author of the given work/chapter, in which the copyrighted material is used. This permission constitutes a non-transferable license and, as such, only applies to The Interaction-Design.org Foundation. Therefore, no part of this material may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, recording or otherwise without prior written permission of the copyright holder.
  14. AllRightsReservedUsedWithoutPermission:
        All Rights Reserved. Non-free, copyrighted materials used without permission. The materials are used without permission of the copyright holder because the materials meet the legal criteria for Fair Use and/or because The Interaction-Design.org Foundation has not been able to contact the copyright holder. The most common cases are: 1) Cover art: Cover art from various items, for identification only in the context of critical commentary of that item (not for identification without critical commentary). 2) Team and corporate logos: For identification. 3) Other promotional material: Posters, programs, billboards, ads: For critical commentary. 4) Film and television screen shots: For critical commentary and discussion of the cinema and television. 5) Screenshots from software products: For critical commentary. 6) Paintings and other works of visual art: For critical commentary, including images illustrative of a particular technique or school. 7) Images with iconic status or historical importance: As subjects of commentary. 8) Images that are themselves subject of commentary.
  15. Pd:
        Public Domain (information that is common property and contains no original authorship)
  16. Trademarks and logos:
        All trademarks, logos, service marks, collective marks, design rights, personality rights or similar rights that are mentioned, used or cited on Interaction-Design.org are the property of their respective owners. The use of any trademark on Interaction-Design.org does not vest in the author or The Interaction-Design.org Foundation any trademark ownership rights in such trademarks, nor does the use of such trademarks imply any affiliation with or endorsement of The Interaction-Design.org Foundation and its authors by such owners. As such The Interaction-Design.org Foundation can not grant any rights to use any otherwise protected materials. Your use of any such or similar incorporeal property is at your own risk.

In addition, content linked from a page is not covered by one of our licenses unless specifically noted. For example, pages may link to videos or slide decks that are not covered. The design of Interaction-Design.org (graphics, html, client-side scripts, etc.) is copyright of Mads Soegaard.

iv. The Site Terms and Conditions

Please read these terms and conditions (the "Terms") carefully before using Interaction-Design.org. By using Interaction-Design.org you signify your consent to these Terms. If you do not agree to the Terms please do not use Interaction-Design.org. The Terms addresses your legal rights and obligations and includes important disclaimers and choice of law and forum provisions. Please read carefully.

1. Ownership of Interaction-Design.org

Interaction-Design.org is owned and operated by The Interaction-Design.org Foundation, a privately held corporation incorporated under the laws of Denmark, with office in Aarhus, Denmark.

Address:
The Interaction-Design.org Foundation
Att: Mads Soegaard
Chr. Molbechs Vej 4
DK-8000 Aarhus C.
Denmark

2. Choice of Law and Forum Provisions

Interaction-Design.org is run by The Interaction-Design.org Foundation, a privately held corporation residing in Aarhus, Denmark. You agree that these Terms and your use of Interaction-Design.org are governed by the laws of Denmark. You hereby consent to the exclusive jurisdiction and venue of the courts, tribunals, agencies and other dispute resolution organizations in Denmark in all disputes

  1. arising out of, relating to, or concerning Interaction-Design.org, The Interaction-Design.org Foundation, and/or these Terms
  2. in which Interaction-Design.org, The Interaction-Design.org Foundation, and/or these Terms is an issue or a material fact
  3. or in which Interaction-Design.org, The Interaction-Design.org Foundation, and/or these Terms is referenced in a paper filed in a court, tribunal, agency or other dispute resolution organization.

The Interaction-Design.org Foundation has endeavoured to comply with all legal requirements known to it in creating and maintaining Interaction-Design.org, but makes no representation that materials on Interaction-Design.org are appropriate or available for use in any particular jurisdiction. You are responsible for compliance with applicable laws. Any use in contravention of this provision or any provision of these Terms is at your own risk and, if any part of these Terms is invalid or unenforceable under applicable law, the invalid or unenforceable provision will be deemed superseded by a valid, enforceable provision that most closely matches the intent of the original provision and the remainder of these Terms shall govern such use.

3. Liability

Your use of and browsing Interaction-Design.org is at your own risk. The Interaction-Design.org Foundation does not warrant that the software used for Interaction-Design.org, and the information, material, and content on it, or any other services provided by means of Interaction-Design.org are error-free, or that their use will be uninterrupted. The Interaction-Design.org Foundation expressly disclaims all warranties related to the above-mentioned subject matter, including, without limitation, those of accuracy, condition, merchantability and fitness for particular purpose. Notwithstanding anything to the contrary on Interaction-Design.org, in no event shall The Interaction-Design.org Foundation be liable for any loss of profits, revenues, indirect, special, incidental, consequential, or other similar damages arising out of or in connection with Interaction-Design.org or out of the use of any of the services proposed by means of Interaction-Design.org.

4. Updates

The Interaction-Design.org Foundation reserves the unilateral right to update, modify, change and alter its Site Terms and Conditions as well as Copyright Terms at any time. All such updates, modifications, changes and alterations are binding on all users and browsers of Interaction-Design.org and will be posted here.

5. Legal Disclaimer

The Interaction-Design.org Foundation and its authors make no representations as to accuracy, completeness, currentness, suitability, or validity of any information, material, or content on Interaction-Design.org.

THE MATERIAL AND CONTENT POSTED ON INTERACTION-DESIGN.ORG ARE PROVIDED "AS IS" WITHOUT ANY EXPRESS WARRANTY OR IMPLIED WARRANTY OF ANY KIND INCLUDING WARRANTIES OF MERCHANTABILITY, NON-INFRINGEMENT OF INTELLECTUAL PROPERTY, OR FITNESS FOR ANY PARTICULAR PURPOSE. IN NO EVENT SHALL THE INTERACTION-DESIGN.ORG FOUNDATION BE LIABLE FOR ANY DAMAGES WHATSOEVER (INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS OF PROFITS, BUSINESS INTERRUPTION, LOSS OF INFORMATION) ARISING OUT OF THE USE OF OR INABILITY TO USE THE MATERIALS, EVEN IF THE INTERACTION-DESIGN.ORG FOUNDATION HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

Because some jurisdictions prohibit the exclusion or limitation of liability for consequential and or incidental damages, the above limitation may not apply to you. Furthermore, The Interaction-Design.org Foundation does not warrant the accuracy or completeness of information of links or other items contained within these materials that have been provided by third parties.

6. Provision regarding change in attribution of copyrighted materials

Please contact us at mads@interaction-design.org if you, or your organization, wish to correct or change attribution or presentation of any image/material used on Interaction-Design.org, which you, or your organization, are the rightful copyright holder of. We will request that you submit proof of your ownership of the copyright on this material but will act immediately on any reasonable request.

7. Notice and prodecure for claims of copyright infringement

Every effort has been made by the individual contributing authors as well as The Interaction-Design.org Foundation to discover and contact copyright holders of artwork/illustrations/content used on Interaction-Design.org. To the extent that a copyright holder could not be found or an inadvertent permissions or copyright error was made, The Interaction-Design.org Foundation stands ready to remove content upon notice and request by a copyright holder. In the case that you believe that any content or other material provided through Interaction-Design.org infringes your copyright, you should notify The Interaction-Design.org Foundation of your infringement claim in accordance with the procedure set forth below.

We will process each notice of alleged infringement which The Interaction-Design.org Foundation receives and take appropriate action in accordance with applicable intellectual property laws. A notification of claimed copyright infringement should be emailed to mads@interaction-design.org (subject: "Takedown Request"). You may also contact us by mail at:

The Interaction-Design.org Foundation
Att: Mads Soegaard
Chr. Molbechs Vej 4
DK-8000 Aarhus C.
Denmark

To be effective, the notification must be in writing and contain the following information:

  1. an electronic or physical signature of the copyright owner or the person authorized to act on behalf of the owner of the copyright interest
  2. a description of the copyrighted work that you claim has been infringed
  3. a description of where the material that you claim is infringing is located on Interaction-Design.org that is reasonably sufficient to enable us to identify and locate the material;
  4. how The Interaction-Design.org Foundation can contact you, such as your address, telephone number, and email address
  5. a written statement by you that you have a good faith belief that the disputed use is not authorized by the copyright owner, its agent, or the law
  6. if you represent a publisher, a written statement by you that you have a good faith belief that the material has not been placed in the public domain, or licenced under another licence, before you acquired the copyright as this would possibly invalidate your copyright
  7. and a statement by you, made under penalty of perjury, that the above information in your notice is accurate and that you are the copyright owner or authorized to act on the copyright owner's behalf.

8. Trademarks and other rights

All trademarks, logos, service marks, collective marks, design rights, personality rights or similar rights that are mentioned, used or cited on Interaction-Design.org are the property of their respective owners. The use of any trademark on Interaction-Design.org does not vest in the author or The Interaction-Design.org Foundation any trademark ownership rights in such trademarks, nor does the use of such trademarks imply any affiliation with or endorsement of The Interaction-Design.org Foundation and its authors by such owners. As such The Interaction-Design.org Foundation can not grant any rights to use any otherwise protected materials. Your use of any such or similar incorporeal property is at your own risk.

9. Screenshots

Screenshots of copyrighted computer software, for which the copyright is held by the author(s) or the company that created the software, is believed to fall under the fair use doctrine in the US (and similar laws in other countries). It is believed that reproduction for purposes such as criticism, comment, news reporting, teaching, or research is not copyright infringement. If you reuse screenshots, as well as any other information on Interaction-Design.org, you do so at your own risk and under the copyright laws of your country.

10. Copyright of Abstracts

Abstracts in the Wiki Bibliography (/references/) are submitted by their authors who use the wiki to make their research as accessible as possible. When a page on Interaction-Design.org cites/references/lists a work from the bibliography, its abstract is included. However, abstracts have varying copyrights depending which publisher the work is published through. You should assume that an abstract is copyright, all rights reserved, of its publisher and/or author and therefore always use/cite abstracts according to Fair Use. You may visit the publisher's website to learn about the specific copyright terms (e.g. ACM, IEEE, or Springer) or contact the author directly. Bottom line: Cite/use abstracts according to the principles of fair use as it may otherwise be construed as a copyright infringement and subject to legal action.

11. User Submissions / User Content

You understand and acknowledge that additions to the Wiki Bibliography (including article abstracts), additions the Conference Calendar (including conference descriptions), user-contributed notes on each page (including text, photographs, graphics), or other materials posted by users on Interaction-Design.org ("Content") are the sole responsibility of the person from whom such Content originated. This means that you, and not The Interaction-Design.org Foundation, are entirely responsible for all Content that you upload, post or otherwise make available to other users of Interaction-Design.org.

When submitting content to Interaction-Design.org, you agree to not:

  1. impersonate any person or entity or falsely state or otherwise misrepresent your affiliation with a person or entity;
  2. upload, post or otherwise make available any Content that you do not have a right to make available under any law or under contractual or fiduciary relationships (such as inside information, proprietary and confidential information learned or disclosed as part of employment relationships or under nondisclosure agreements);
  3. upload, post or otherwise make available any Content that infringes any patent, trademark, trade secret, copyright or other proprietary rights ("Rights") of any party;
  4. upload, post or otherwise make available any Content that is unlawful, harmful, threatening, abusive, harassing, tortious, defamatory, vulgar, obscene, libelous, invasive of another's privacy, hateful, or racially, ethnically or otherwise objectionable;

You acknowledge that The Interaction-Design.org Foundation shall have the right to remove any Content that violates these Site Terms and Conditions or is otherwise objectionable.

12. Third Party Websites

If we provide links or pointers to other websites, no inference or assumption should be made that The Interaction-Design.org Foundation operates, controls, or is otherwise connected with these websites. When you click on a link within Interaction-Design.org, we will not warn you that you have left a Site and are subject to the terms and conditions (including privacy policies) of the destination website. In some cases it may be less obvious than others that you have left a Site and reached another website. Please be careful to read the terms of use and privacy policy of any website before you provide any confidential information or engage in any transactions. You should not rely on these Terms for another website. The Interaction-Design.org Foundation is not responsible for the content or practices of any other website. By using Interaction-Design.org, you acknowledge and agree that The Interaction-Design.org Foundation is not responsible or liable to you for any content or other materials hosted and served from any third party website.

13. Email communication: Confidential and proprietary information notice

Email messages sent from members of The Interaction-Design.org Foundation, including emails generated from the use of the interaction-design.org website, are proprietary to The Interaction-Design.org Foundation, and are intended solely for the use of the individual to whom they are addressed. Such messages may contain privileged or confidential information and should not be circulated or used for any purpose other than for what they are intended. If you receive a message from a member of The Interaction-Design.org Foundation in error, please notify the sender immediately. If you are not the intended recipient, you are hereby notified that you are strictly prohibited from using, copying, altering, or disclosing the contents of the message. The Interaction-Design.org Foundation accepts no responsibility for loss or damage arising from the use of the information transmitted by email message including damage from virus.

14. Usage conditions

Please make sure that you understand that the information provided by The Interaction-Design.org Foundation is being provided freely, and that no kind of agreement or contract is created between you and the owners, partners, users, or authors of this site, the owners of the servers upon which it is housed, the individual contributors of the The Interaction-Design.org Foundation, any project administrators, sysops or anyone else who is in any way connected with this project. If you choose to use or copy anything from from this site it does not create or imply any contractual or extracontractual liability on the part of The Interaction-Design.org Foundation or any of its members, partners, sponsors, contributors or other users. Your use of any such or similar incorporeal property is at your own risk.

15. Legal Disputes

Any dispute arising from the use of Interaction-Design.org or the interpretation of the terms is governed by the laws of Denmark, and shall be settled by the courts of Denmark. All communications regarding legal matters must be made in writing to

The Interaction-Design.org Foundation
Att: Mads Soegaard
Chr. Molbechs Vej 4
DK-8000 Aarhus C.
Denmark


 

About the author

Picture of Eelke Folmer. Copyright of Eelke Folmer and Interaction-Design.org through the Creative Commons Share-Alike licence.
Eelke Folmer is an assistant Professor at the University of Nevada in Reno. Previously he worked as a postdoctoral fellow in the Software Engineering / Games Group at the University of Alberta. He received a PhD degree from the University of Groningen where he worked on the European Union funded Software Architecture for Usability (STATUS) project.   His research interests revolve a...   
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