High availability versus disaster recovery

High availability is again different from disaster recovery; however, the difference can be very subtle. High availability is a function of the application being in a consumable state as and when the user asks for it. So, it is designed for operations that come before a disaster, while disaster recovery is a function that comes into the picture after a disaster. Disaster recovery refers to the architecture implementation through which services are up and running after a disaster, while high availability takes care of availability prior to a disaster. Disaster recovery includes data backup and archived and dormant servers across continents, while high availability consists of load balancers, distribution of load, and active-passive and active-active redundancy.