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.