Experience definitions provide multiple user experiences within a single portal. An experience definition defines certain elements of a user experience, such as adaptive page layout settings, branding style, and navigation. An experience rule defines the conditions that, when met, display the associated experience definition to a user.
When you create an experience rule, you must also place it in rank order in relation to existing rules. The first rule to evaluate to true will be applied. For example, you might create a rule that says that users in the Marketing group see the user interface defined in the Marketing experience definition, and another rule that says that users in the Management group see the user interface defined in the Management experience definition. Since some users may be in both groups, you may decide that you want the Management experience definition to have priority. In this case, you order the two rules so that the Management experience rule is above the Marketing experience rule.
If you want to have different user experiences for different audiences of guest users (users that have not logged in), you might want to create several guest users and assign them different experience definitions. For an example, see the Guest Users section in About Users.