Disk storage

The recording employs various electronic, magnetic, optical, or mechanical changes to the disk's surface layer.

Improvements in mechanical design and manufacture allowed smaller and more precise heads, meaning that more tracks could be stored on each of the disks.

Advancements in data compression methods permitted more information to be stored in each of the individual sectors.

The information is sent from the computer processor to the BIOS into a chip controlling the data transfer.

The data is then passed to a chip on the circuit board that controls the access to the drive.

The drive is divided into sectors of data stored onto one of the sides of one of the internal disks.

A file is not stored in a linear manner; rather, it is held in the best way for quickest retrieval.

Storage devices intended for desktop and mobile computers typically use ATA (PATA) and SATA interfaces.

Enterprise systems and high-end storage devices will typically use SCSI, SAS, and FC interfaces in addition to some use of SATA.

Six hard disk drives
Three floppy disk drives
A CD-ROM (optical) disc drive
Comparison of several forms of disk storage showing tracks (not-to-scale); green denotes start and red denotes end.
* Some CD-R(W) and DVD-R(W)/DVD+R(W) recorders operate in ZCLV, CAA or CAV modes.