Backup and archiving perform separate functions for different reasons, but they are complementary,
and the capabilities of each one can help the other work more effectively. Backup is for recovery,
archiving is for discovery.
Backup stores multiple copies that are each associated with a specific revision of data, and it provides
recovery back to a known good state from a specific point of time. A backup enables recovery from a
situation where data has been lost, corrupted or becomes inaccessible, so it's primarily a safeguard to
facilitate data recovery.
Archiving preserves a single copy in secure immutable storage for a finite time period and provides
ongoing end user access to historical business information. An archive enables compliance with legal
and business data retention policies, as well as supporting eDiscovery.
Finally, email archiving covers business email but not other Microsoft 365 files and projects. Backup for
Microsoft 365 preserves and recovers mailboxes, but it also covers other Microsoft 365 data, including
Teams projects, OneDrive storage and SharePoint sites and libraries.