question - cylinder/heads/sectors/track/blocks

[Conor P. Cahill]

In article <100 at lkbpyr.UUCP>, jonas at lkbpyr.UUCP (Jonas Heyman) writes:
> Hello,
> 
> Could anybody tell me how all this fits together: cylinder,heads,sectors,
> 							block,track.

The disk is composed of several plates (platters) that contain data.  
Each of these plates will usually (if not always) have two sides. A "head"
is required to read and/or write each side of each plate. The plates
are all the same size and rotate around the same core just slightly 
separated (the read/write heads must fit between each plate).

A track is a full circle of data on a single side of a plate.  The side
will have multiple cocentric tracks each of which are broken up into the 
same number of sections (sectors). 

Since the plates sit atop each other in the drive, the collection of
the same track from each side of each plate in the disk is a cylinder.

So each disk     is composed of #_of_heads surfaces
   each cylinder is composed of #_of_heads tracks.
   each track    is composed of #_of_sectors sectors.
   each sector   is usually composed of 512 bytes.
   
A "block" is usually a logical issue not directly associated with 
the low level format of the disk (other that the fact that it is
normally equal to, or a multiple of the size of a sector.
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