# Retention Types

The retention type defines how the retention period is applied to the backup. More information is available from [Veeam's documentation](https://helpcenter.veeam.com/docs/vbo365/guide/retention_policy.html?ver=60).

-   Snapshot Based\
    Each restore point represents the snapshot (actual state) of each mailbox, library or folder at the time of backup. Items will be deleted from backup once the last restore point they are contained within leaves the retention period.
-   Item Level\
    Individual items will be deleted from backup once their creation or last modification date exceeds the data retention period. This is similar to how classic documents archive works, and is useful if you need to ensure that items are not stored in backup longer than required.