Hello,
Salesforce Help defines Analytic Snapshots as “allowing you to load data from a Custom Report to a Custom Object on a regularly scheduled basis.” This in turn allows you to create Reports and Dashboards based on the data in the Custom Object.
Analytic Snapshots are comprised of three things:
A source Report of type Tabular or Summary
A Custom Object with fields matching the columns in the source Report
An Analytic Snapshot definition, which maps fields and schedules the snapshot runs
Thanks.