What is an Audience?
An "Audience" is a group of visitors that you want to be included in your experience, being a test or personalization.
Audience Dialog Sections
The Audience section of your experience setting on your "Experience Summary has three different sections you should be aware of: 1) Presets, 2) Saved Audiences, 3) New Audience.
The Presets section allows you to choose from pre-built audiences. This will help you speed the configuration of your experiment audiences.
Saved Audiences Section
This is the place where you will find the audiences you already created.
New Audience... Section
This section is where you can create your own audiences if none of the Presets fit your requirements.
You can find more documentation about the sections of the tabs in the following articles:
These instructions pertain to the new Audiences Interface. This applies to all experiences created after the new Legacy Audiences launch before September 16th, 2017
Go here to find the documentation related to the legacy audiences interface.