Methods of Storage • Magnetic • Flash • Optical
Magnetic Storage • Storage device that encodes data as microscopic magnetized needles on the disk's surface • The hard disk is the most common magnetic storage device
Flash Storage A type of constantly-powered memory that can be erased and reprogrammed in a single action or “flash.” Described as “solid-state” memory because there are no mechanical (moving) parts. Also known as a pen drive, thumb drive, jump drive. Storage cards for digital cameras use flash memory.
Optical Storage • Storage device that records data by burning microscopic holes in the surface of the disk with a laser • Compact disks • Digital video disks • Blu-ray disks
Compact Disk • CD-ROM: stores information permanently; cannot be changed; typical media used for software ; 650MB capacity • CD-R: recordable; can record multiple times but cannot be erased or overwritten; 650-700 MB capacity • CD-RW: rewritable; can store, erase, and replace data information like a floppy disk or hard drive; 700 MB capacity is typical.
Digital Video Disk • DVD-ROM—typical storage capacity 17GB; permanent storage • DVD-R, DVD+R, DVD±R—recordable, can record multiple times but cannot be erased or overwritten; 4.7 GB capacity • DVD-RW, DVD+RW, DVD±RW—can store, erase, and replace datainformation like a floppy disk or hard drive; 4.7 GB capacity is typical.
Blu-ray Disk • High capacity optical disk that has a storage capacity of 25GB. • Has recordable and rewritable disks just like CDs and DVDs. How Blu-ray Discs Work