What does the X in cNd0sX stand for?

[Joe Grant]

I have a question about the meaning of the X in cNd0sX used for the
disk device in /dev/dsk. I'm currently trying to setup a file system
on a SyQuest removable cartridge which I initialized using MicroNet
Utility 4.4 and partitioned with a single partition (partition 0).
When I read the manual it talks of using the /dev/dsk/cNd0sX device
address where N is the SCSI ID of the drive and X is the slice. What
do they mean by slice? Does it correspond to a partition, i.e in this 
case cNd0s0, or is it something else entirely? In one part of the manual
it does say that slice 3,4,5 and 6 can be used for /user or /users
while slice 2 is for /usr, what do they mean by this, what are slices
0 and 1 reserved for, and what happens after slice 7? 

Any help would be appreciated.

Joe Grant
-- 
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