Editing Disk storage (section)

== Basic terminology ==
<!-- This should be NOT specific to hard drives, there is a separate page for that! Please keep it general (hard disk, floppy, optical, ...). -->
;Disk : Generally refers to magnetic media and devices.
; Disc : Required by trademarks for certain optical media and devices. 
; Platter : An individual recording disk. A hard disk drive contains a set of platters. Developments in optical technology have led to multiple recording layers on [[Comparison of high definition optical disc formats|DVD]]s.
; [[Spindle (hard disk drive)|Spindle]] : the spinning [[axle]] on which the platters are mounted.
; Rotation : Platters rotate; two techniques are common:
:* [[Constant angular velocity]] (CAV) keeps the disk spinning at a fixed rate, measured in revolutions per minute (RPM). This means the heads cover more distance per unit of time on the outer tracks than on the inner tracks. This method is typical with computer hard drives.
:*[[Constant linear velocity]] (CLV) keeps the distance covered by the heads per unit time fixed. Thus the disk has to slow down as the arm moves to the outer tracks. This method is typical for [[Compact disc|CD]] drives.
; Track : The circle of recorded data on a single recording surface of a platter.
<!--  too much HDD specific 
; Cylinder : In a multi-head drive, all the tracks under the heads for a given arm position can be read without seek delay. The operating system treats the contents of those tracks as a single cylinder. 
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; [[Disk sector|Sector]] : A segment of a track
; Low level [[disk format|formatting]] : Establishing the tracks and sectors.
; Head : The device that reads and writes the information—magnetic or optical—on the disk surface.
; Arm : The mechanical assembly that supports the head as it moves in and out.
; [[Seek time]] : Time needed to move the head to a new position (specific track).
; [[Rotational latency]] : Average time, once the arm is on the right track, before a head is over a desired sector.
; [[Bit rate|Data transfer rate]] : The rate at which user data bits are transferred from or to the medium. Technically, this would more accurately be entitled the [[Bit rate#Gross bit rate|"gross" data transfer rate]]. 
<!--- Obsolete, even for floppies
; Interleave : The spacing between sectors. Sequential sectors were spaced on the media to enable the next sector to be in the correct position under the head once the host was ready to read it. At an interleave factor of 3:1, three full rotations would be required to read an entire track. Due to technological advances almost all hard disk drives since [[Compaq]] and [[Western Digital]] defined the [[AT Attachment]] standard have used an interleave factor of 1:1. Floppy disks are still usually interleaved.
-->
<!-- ==Standard Disk Sizes==
The IDEMA (International Disk Drive Equipment and Materials Association)<ref>
[http://www.idema.org/_smartsite/modules/local/data_file/show_file.php?cmd=download&data_file_id=1066 Document LBA01-02] LBA Count for IDE Hard Disk Drives</ref> defines the standard disk sizes for IDE drives as:
* Total size in bytes = LBA ([[Logical Block Addressing]]) count * 512 bytes per block
* LBA count = (97696368) + (1953504 * (Desired Capacity in Gbytes – 50.0))
{|align="center" class="wikitable"
|-bgcolor="#ccccff" -align="right"
| GB
|  LBA
|   bytes
|    kibibytes
|     mebibytes
|      gibibytes
|-align=right
| 50
|  97696368
|   50,020,540,416
|    48,848,184
|     47,703.3
|      46.585
|-align=right
| 60
|  117231408
|   60,022,480,896
|    58,615,704
|     57,241.9
|      55.900
|-align=right
| 80
|  156301488
|   80,026,361,856
|    78,150,744
|     76,319.0
|      74.530
|-align=right
| 100
|  195371568
|   100,030,242,816
|    97,685,784
|     95,396.2
|      93.160
|-align=right
| 120
|  234441648
|   120,034,123,776
|    117,220,824
|     114,473.4
|      111.790
|-align=right
| 160
|  312581808
|   160,041,885,696
|    156,290,904
|     152,627.8
|      149.051
|-align=right
| 180
|  351651888
|   180,045,766,656
|    175,825,944
|     171,705.0
|      167.681
|-align=right
| 200
|  390721968
|   200,049,647,616
|    195,360,984
|     190,782.2
|      186.311
|-align=right
| 250
|  488397168
|   250,059,350,016
|    244,198,584
|     238,475.1
|      232.886
|-align=right
| 300
|  586072368
|   300,069,052,416
|    293,036,184
|     286,168.1
|      279.461
|-align=right
| 320
|  625142448
|   320,072,933,376
|    312,571,224
|     305,245.4
|      298.091
|-align=right
| 400
|  781422768
|   400,088,457,216
|    390,711,384
|     381,554.0
|      372.611
|-align=right
| 500
|  976773168
|   500,107,862,016
|    488,386,584
|     476,940.0
|      465.762
|} -->