Campaigns is the part of Engage where you can send messages to multiple customers at the same time. They consist of audience, content and schedule:
The audience of your campaign is the group of customers who will receive it.
Message type is the kind of message the customers will receive in your campaign. In Engage, you can either use a predefined template or compose the message freely from scratch.
Campaigns in Engage can be sent right away or scheduled for sending at the time of your choice.