Interface design is involved in a wide range of projects, from computer systems, to cars, to commercial planes; all of these projects involve much of the same basic human interactions yet also require some unique skills and knowledge. As a result, designers tend to specialize in certain types of projects and have skills centered on their expertise, whether it is software design, user research, web design, or industrial design.
Good user interface design facilitates finishing the task at hand without drawing unnecessary attention to itself. Graphic design and typography are utilized to support its usability, influencing how the user performs certain interactions and improving the aesthetic appeal of the design; design aesthetics may enhance or detract from the ability of users to use the functions of the interface.1 The design process must balance technical functionality and visual elements (e.g., mental model) to create a system that is not only operational but also usable and adaptable to changing user needs.
Compared to UX design, UI design is more about the surface and overall look of a design. User interface design is a craft in which designers perform an important function in creating the user experience. UI design should keep users informed about what is happening, giving appropriate feedback in a timely manner. The visual look and feel of UI design sets the tone for the user experience.2 On the other hand, the term UX design refers to the entire process of creating a user experience.
Don Norman and Jakob Nielsen said:
It's important to distinguish the total user experience from the user interface (UI), even though the UI is obviously an extremely important part of the design. As an example, consider a website with movie reviews. Even if the UI for finding a film is perfect, the UX will be poor for a user who wants information about a small independent release if the underlying database only contains movies from the major studios.3
User interface design requires a good understanding of user needs. It mainly focuses on the needs of the platform and its user expectations. There are several phases and processes in the user interface design, some of which are more demanded upon than others, depending on the project.4 The modern design thinking framework was created in 2004 by David M. Kelley, the founder of Stanford’s d.school, formally known as the Hasso Plattner Institute of Design.5 EDIPT is a common acronym used to describe Kelley’s design thinking framework—it stands for empathize, define, ideate, prototype, and test.6 Notably, the EDIPT framework is non-linear, therefore a UI designer may jump from one stage to another when developing a user-centric solution. Iteration is a common practice in the design thinking process; successful solutions often require testing and tweaking to ensure that the product fulfills user needs.7
Common areas of interest include:
The Nielsen Norman Group, co-founded by Jakob Nielsen and Don Norman in 1998, promotes user experience and interface design education. Jakob Nielsen pioneered the interface usability movement and created the "10 Usability Heuristics for User Interface Design."9 Usability is aimed at defining an interface’s quality when considering ease of use; an interface with low usability will burden a user and hinder them from achieving their goals, resulting in the dismissal of the interface. To enhance usability, user experience researchers may conduct usability testing—a process that evaluates how users interact with an interface. Usability testing can provide insight into user pain points by illustrating how efficiently a user can complete a task without error, highlighting areas for design improvement.10
The dynamic characteristics of a system are described in terms of the dialogue requirements contained in seven principles of part 10 of the ergonomics standard, the ISO 9241. This standard establishes a framework of ergonomic "principles" for the dialogue techniques with high-level definitions and illustrative applications and examples of the principles. The principles of the dialogue represent the dynamic aspects of the interface and can be mostly regarded as the "feel" of the interface.
The concept of usability is defined of the ISO 9241 standard by effectiveness, efficiency, and satisfaction of the user.
Part 11 gives the following definition of usability:
Effectiveness, efficiency, and satisfaction can be seen as quality factors of usability. To evaluate these factors, they need to be decomposed into sub-factors, and finally, into usability measures.
The information presented is described in Part 12 of the ISO 9241 standard for the organization of information (arrangement, alignment, grouping, labels, location), for the display of graphical objects, and for the coding of information (abbreviation, colour, size, shape, visual cues) by seven attributes. The "attributes of presented information" represent the static aspects of the interface and can be generally regarded as the "look" of the interface. The attributes are detailed in the recommendations given in the standard. Each of the recommendations supports one or more of the seven attributes.
The user guidance in Part 13 of the ISO 9241 standard describes that the user guidance information should be readily distinguishable from other displayed information and should be specific for the current context of use.
User guidance can be given by the following five means:
User interface design has been a topic of considerable research, including on its aesthetics.11 Standards have been developed as far back as the 1980s for defining the usability of software products. One of the structural bases has become the IFIP user interface reference model.
The model proposes four dimensions to structure the user interface:
This model has greatly influenced the development of the international standard ISO 9241 describing the interface design requirements for usability. The desire to understand application-specific UI issues early in software development, even as an application was being developed, led to research on GUI rapid prototyping tools that might offer convincing simulations of how an actual application might behave in production use.12 Some of this research has shown that a wide variety of programming tasks for GUI-based software can, in fact, be specified through means other than writing program code.13
Research in recent years is strongly motivated by the increasing variety of devices that can, by virtue of Moore's law, host very complex interfaces.14
Norman, D. A. (2002). "Emotion & Design: Attractive things work better". Interactions Magazine, ix (4). pp. 36–42. Archived from the original on Mar 28, 2019. Retrieved 20 April 2014 – via jnd.org. https://web.archive.org/web/20190328233305/https://jnd.org/emotion_design_attractive_things_work_better/ ↩
Roth, Robert E. (April 17, 2017). "User Interface and User Experience (UI/UX) Design". Geographic Information Science & Technology Body of Knowledge. 2017 (Q2). doi:10.22224/gistbok/2017.2.5. https://doi.org/10.22224%2Fgistbok%2F2017.2.5 ↩
"The Definition of User Experience (UX)". Nielsen Norman Group. Retrieved 13 February 2022. https://www.nngroup.com/articles/definition-user-experience/ ↩
Wolf, Lauren (23 May 2012). "6 Tips for Designing an Optimal User Interface for Your Digital Event". INXPO. Archived from the original on 16 June 2013. Retrieved 22 May 2013. https://archive.today/20130616121623/http://web.inxpo.com/casting-calls/bid/105506/6-Tips-for-Designing-an-Optimal-User-Interface-for-Your-Digital-Event ↩
Dam, Rikke Friis; Siang, Teo Yu (2024-10-01). "The History of Design Thinking". The Interaction Design Foundation. Retrieved 2024-10-01. https://www.interaction-design.org/literature/article/design-thinking-get-a-quick-overview-of-the-history ↩
"The Stanford Design Thinking Process – Make:Iterate". 2022-12-15. Retrieved 2024-10-10. https://makeiterate.com/the-stanford-design-thinking-process/ ↩
Dam, Rikke Friis (2024-10-01). "The 5 Stages in the Design Thinking Process". The Interaction Design Foundation. Retrieved 2024-10-01. https://www.interaction-design.org/literature/article/5-stages-in-the-design-thinking-process ↩
Ann Blandford. "Semi-structured qualitative studies". The Encyclopedia of Human-Computer Interaction, 2nd Ed. Interaction Design Foundation. Retrieved 20 April 2014. http://www.interaction-design.org/encyclopedia/semi-structured_qualitative_studies.html ↩
"10 Usability Heuristics for User Interface Design". Nielsen Norman Group. Retrieved 2024-10-09. https://www.nngroup.com/articles/ten-usability-heuristics/ ↩
"Usability 101: Introduction to Usability". Nielsen Norman Group. Retrieved 2024-10-09. https://www.nngroup.com/articles/usability-101-introduction-to-usability/ ↩
"The role of context in perceptions of the aesthetics of web pages over time". International Journal of Human–Computer Studies. 2009-01-05. Retrieved 2009-04-02. http://portal.acm.org/citation.cfm?id=1464532.1465384&coll=GUIDE&dl=GUIDE&CFID=27731682&CFTOKEN=18425618 ↩
"The HUMANOID model of interface design". Proceedings CHI'92. 1992. http://citeseer.ist.psu.edu/old/szekely92facilitating.html ↩
"Creating user interfaces using programming by example, visual programming, and constraints". ACM. 1990-04-11. Retrieved 2009-04-02. http://portal.acm.org/citation.cfm?id=78942.78943&coll=GUIDE&dl=GUIDE&CFID=27731682&CFTOKEN=18425618 ↩
"Past, present, and future of user interface software tools". ACM. 2000-03-01. Retrieved 2009-04-02. http://portal.acm.org/citation.cfm?id=344949.344959&coll=GUIDE&dl=GUIDE&CFID=27731682&CFTOKEN=18425618 ↩