Hi @Shruti1 ,
Following is the definition of your concerned terms:
Campaign: A campaign enables you to gather all the marketing activities of your choice under a single entity. A campaign may contain emails, SMS, push notifications, direct mail, workflows, and landing pages. (source)
Workflow: Adobe Campaign includes a workflow module that empowers you to orchestrate the full range of processes and tasks across the different modules of the application server. This comprehensive graphical environment lets you design processes including segmentation, campaign execution, file processing, human participation, etc. The workflow engine executes and tracks these processes. (source)
Delivery: Delivery is the feature in Adobe campaign that enables you to reach out to your recipients via like Email, SMS, Push, Direct Mail, etc multiple communication channels.
Br,
Shubham
