Graphic design may be utilized to apply a theme or style to the interface without compromising its usability. 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.

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 interaction yet also require some unique skills and knowledge. As a result, designers tend to specialize in certain types of projects and have skills centered around their expertise, whether that be software design, user research, web design, or industrial design.

Processes

There are several phases and processes in the user interface design, some of which are more demanded upon than others, depending on the project. (Note: for the remainder of this section, the word system is used to denote any project whether it is a web site, application, or device.)

• Functionality requirements gathering – assembling a list of the functionality required of the system to accomplish the goals of the project and the potential needs of the users.
• User analysis – analysis of the potential users of the system either through discussion with people who work with the users and/or the potential users themselves. Typical questions involve:
  • What would the user want the system to do?
  • How would the system fit in with the user’s normal workflow or daily activities?
  • How technically savvy is the user and what similar systems does the user already use?
  • What interface look & feel styles appeal to the user?
• Information architecture – development of the process and/or information flow of the system (i.e. for phone tree systems, this would be an option tree flowchart and for web sites this would be a site flow that shows the hierarchy of the pages).
• Prototyping – development of wireframes, either in the form of paper prototypes or simple interactive screens. These prototypes are stripped of all look & feel elements and most content in order to concentrate on the interface.
• Usability testing – testing of the prototypes on an actual user—often using a technique called talk aloud protocol where you ask the user to talk about their thoughts during the experience.
• Graphic Interface design – actual look & feel design of the final graphical user interface (GUI). It may be based on the findings developed during the usability testing if usability is unpredictable, or based on communication objectives and styles that would appeal to the user. In rare cases, the graphics may drive the prototyping, depending on the importance of visual form versus function. If the interface requires multiple skins, there may be multiple interface designs for one control panel, functional feature or widget. This phase is often a collaborative effort between a graphic designer and a user interface designer, or handled by one who is proficient in both disciplines.

User interface design requires a good understanding of user needs.

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article “User interface design”.