When you want to put a standby database into managed recovery (which is the most common form of automatic recovery), you start SQL Plus and issue the managed recovery command, but then what? You've got an SQL Plus session that has to be left running - simple mistakes like sending it an interrupt signal could do nasties to your standby database.
But now there is an easier way in 9i. Simply issue
SQL> recover managed standby disconnect
and the managed recovery commences without the overhead and inconvenience of an SQL Plus session left behind