What is the difference between start and enable in the Oracle RAC srvctl?

In the Oracle 12c documentation it was not clear what is the difference between the *srvctl start* and *srvctl enable* commands for services associated with a database. In the view **dba_service** a database that has a service already started, has the column *ENABLED* with *NO*, what I noticed is that when a RAC service has already started and you try to enable it, it informs you that it is already enabled. srvctl enable service -d mydb -s myservice PRCC-1010: myservice was already enabled PRCR-1002: Resource ora.mydb.myservice.svc is already enabled