SAP Marketing Cloud comes with a marketing-specific license of SAP Analytics Cloud, embedded edition or SAP Analytics Cloud which allows you to access all relevant business data and integrated analytics directly into your business processes, visualized on one screen. In SAP Marketing Cloud, you can either use the pre-delivered standard marketing analytics content, or you can create your own analytics content based on your data sources.
The Analytics and Report Gallery application is based on the use of the analytic capabilities of SAP Analytics Cloud. The Analytics and Report Gallery app is a central entry point where you can access all analytics and reporting content like analytics stories and operational reports.
For more information, see the documentation about the Analytics and Report Gallery.