for example:

Insert links using the defaults:
   update-rc.d foobar defaults
Equivalent command using explicit argument sets:
   update-rc.d foobar start 20 2 3 4 5 . stop 20 0 1 6 .
More typical command using explicit argument sets:
   update-rc.d foobar start 30 2 3 4 5 . stop 70 0 1 6 .
Insert links at default runlevels when B requires A
   update-rc.d script_for_A defaults 80 20
   update-rc.d script_for_B defaults 90 10
Insert a link to a service that (presumably) will not be needed by any other daemon
   update-rc.d top_level_app defaults 98 02
Insert links for a script that requires services that start/stop at sequence number 20
   update-rc.d script_depends_on_svc20 defaults 21 19
Remove all links for a script (assuming foobar has been deleted already):
   update-rc.d foobar remove
Example of disabling a service:
   update-rc.d -f foobar remove
   update-rc.d foobar stop 20 2 3 4 5 .
Example of a command for installing a system initialization-and-shutdown script:
   update-rc.d foobar start 45 S . stop 31 0 6 .
Example of a command for disabling a system initialization-and-shutdown script:
   update-rc.d -f foobar remove
   update-rc.d foobar stop 45 S .
		

set default

update-rc.d nginx defaults
		

remove

update-rc.d -f lighttpd remove
$ sudo update-rc.d -f avahi-daemon remove