When working on a project that targets a specific type of individual or group, or when a site or application is to be used by various types of end user, it is important to have an understanding of who those people are, and what they need to accomplish on your site or with your application. A user persona is a fictional personality derived from user research and describes a typical person within a user group, their possible use, and the ways they might interact with a site or application.

Sometimes referred to as the target market within marketing groups, much of the data collected as part of market research can be combined with interviews of typical users to build a picture of a particular user group.