B2C Commerce includes a set of standard customer groups (everyone, registered customers, and unregistered customers).
Create other customer groups in addition to the standard ones. For example, if you create and activate a promotion that is targeted to registered customers, only a registered customer sees the promotion on the storefront. The registered customers group members are registered but not necessarily logged in. This means that if a registered user's session expires, that user can still qualify for customer groups assigned to registered users. To prevent this, create a dynamic customer group with the condition "Authenticated = true".
Customer groups are assigned to a campaign. Promotions inherit customer group assignments from their parent campaign. When defining a promotion, remove all customer group assignments but not individual customer group assignments from the Promotion configuration page. You can't add unassigned customer groups.
If an active promotion inherits a customer group qualifier of registered customers from its active parent campaign, the promotion is automatically added to the shopping cart of registered customers.
To assign a customer group to a campaign or promotion, see Creating a Campaign and Creating a Promotion