Retention refers to the process of managing backup data by defining rules or policies that specify how long recovery points should be retained and when older data should be deleted. This ensures efficient use of storage resources, compliance with regulatory or organizational requirements, and streamlined backup management.

Key aspects of retention include:

• Storage Optimization: Automatically deletes outdated recovery points to free up space.
• Policy Compliance: Ensures backups are retained for the required duration based on legal or business needs.
• Automation: Simplifies data lifecycle management by applying predefined rules.

Retention policies can range from basic retention, which focuses on a specific number of versions or days, to advanced strategies like GFS (Grandfather-Father-Son), which maintains daily, weekly, monthly, and yearly backups for long-term data availability.