You can use audience in many ways. One of them is to segment customers/users based on their interests. 

Navigate to 'omniCustomers \ Audiences' to manage customer/user audiences and its members. Choose 'Customer Audience' to manage customer audiences and choose 'User Audience' to manage user audiences.

Note: If Customer is connected to the user profile, updating Customer audience selection automatically update user audience selection. The same if you update User which is connected to the Customer, the Customer audiences selection will be update when you update User selection.