Ubuntu 9.04 vs 9.10

I wanted to know what is the logic behind the differences in Ubuntu 9.04 and 9.10...

I mean i am not aware of all the differences, but i came across one which i would like to share.. in 9.04, there is no "init" or "inittab" and there is one "event.d" directory

but in 9.10, we do have an "init" and "init.d" whereas no "event.d"..

I had been researching on this thing because i wanted to change the runlevel of Ubuntu to "1" while startup..

So please help me out here..

And Please CORRECT ME IF I AM WRONG SOMEWHERE WITH WHAT I WROTE...
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