This category revolves around various types of rotating disk computer storage media. The discs may be permanently attached to, or removable from, the computer. For large computer systems such as mainframes and server farms, the discs may be connected to a network, and thus may be situated physically distant from the computers they serve. In the latter setup, rotating discs tends to replace some magnetic tape data storage systems (although tape storage is still^[update] less expensive per data unit stored).

For articles on the drives and devices which use this media see Category:Hard disk computer storage