Answer Description

The Recovery Time Objective (RTO) is the targeted duration of time and a service level within which a business process must be restored after a disruption to avoid a break in business continuity.

Wikipedia

Disaster recovery is the process of maintaining or reestablishing vital infrastructure and systems following a natural or human-induced disaster, such as a storm or battle. It employs policies, tools, and procedures. Disaster recovery focuses on information technology (IT) or technology systems supporting critical business functions as opposed to business continuity. This involves keeping all essential aspects of a business functioning despite significant disruptive events; it can therefore be considered a subset of business continuity. Disaster recovery assumes that the primary site is not immediately recoverable and restores data and services to a secondary site.