Simple ticket to insert a Script in startup

Step one: Create a script in /etc/init.d/ -> This is executed at statup

Step Two: Use the command -> update-rc.d with following syntax

update-rc.d [script-name] start [seq-num] [list-of-run-levels]
In this we have,
[seq-num] = 0 - 99
[list-of-run-levels] is separated by space, and terminated by "."