When you create a rule or deal in the Campaign Center, you can choose to apply it to specific members. For example, you can apply it only to members with a specific tag such as students, VIPs, or members that haven't visited in 2 months.
By default, rules and deals apply to all registered members.
However, you can click to change it to apply to all members (which also includes Pending members who haven't completed their registration payment, and Non-Registered App Users), or to specific members.
You can specify members according to different member attributes. The attributes that you can choose from are the ones in your registration form and additional system ones like tag, if they allow SMS, etc. If you choose multiple member attributes, then ALL of them must be satified for the activity to apply to a member. For example, the member is tagged student AND is an app user.
You can also specify the membership status (i.e., registered, pending, or non-registered app users). For example, if you want to send an in-app message to users that installed the app but haven't yet registered, you would need to apply the rule to non-registered app users. Or if you want to register a member that paid for their membership, you would need to apply the rule to pending members.