In an ideal scenario, all business data will be backed up in real time (or almost real time). In such a scenario, any data lost will be immediately be recovered in full or almost fully from the back ups, and operations will continue with a minimum of pause. In realistic scenarios, however, staff will probably be overburdened with day-to-day operations to back up all data. Even if data is backed up, it might not be tested for recover-ability. In this scenario, data recovery services become a critical requirement.
Data recovery professional can be full-fledged data recovery company with extensive data recovery facilities. Or they could be small individual operators who provide a specialized service to smaller IT installations.