Why is there a cd entry in the fstab?

[Brian McKee]

<short background - oversimplified>
I took a working Hardy box with a CDROM, duplicated the hard drive and
stuck it in a different box with a DVDROM/CDRW.
</background>

The DVD didn't work at all.  Didn't even seem to spin up.  Figuring
bad hardware (first time using that drive) I replaced it with a plain
CDROM.  Still didn't work right, but it would spin up.  You couldn't
eject the tray.  Oddly, if you inserted a cd and went to Computer the
name of the CD would appear on the CD Rom icon, but clicking the icon
would give you an error saying there likely was no media.

While goofing around trying to figure things out I commented out the
entry in the fstab
  dev/scd0       /media/cdrom0      udf,iso9660 user,noauto,exec,utf8 0 0

and it works...

So why is there an entry in the fstab at all?  Is is there just for cd burning?

As of right now, /dev/cdrom1 and /dev/sr0 are linked to /dev/scd0.   I
don't think that's the way it was earlier.

Note it's cdrom0 in the fstab.

Are the cdrom entries generated by udev like the ethernet entries, and
if I swap one they 'autoincrement'   But if that's the case why didn't
the cdrom1 entry get made the first time?

I guess I'm looking for insight into how the whole thing is supposed
to work so I can figure out what happened here.

Brian