Service Dependencies allow services to be started (and stopped) in order. They specify which services or load order groups must be running on the machine before this service can run. For example, if the service FDSvc depends on the pre-requisite service Pre, then Windows will always start Pre before FDSvc during a machine boot-up. Similarly, if both Pre and FDSvc are stopped, then manually starting FDSvc will firstly cause Pre to be automatically started. Similarly, stopping Pre manually will force FDSvc to stop. Interestingly, services dependencies are not used during machine shutdown.
Visit the Dependencies section of the FireDaemon Pro manual to learn more about configuring dependencies.