Recovery point objective (RPO) is the maximum acceptable amount of data loss after an unplanned data-loss incident, expressed as an amount of time. This is generally thought of as the point in time before the event at which data can be successfully recovered -- that is, the time elapsed since the most recent reliable backup.
This can vary from organization to organization. A smaller business might only need a backup since the most recent close of business, while many enterprises have a very short RPO, requiring a backup from the point of failure.
Also see: Recovery Time Objective (RTO)