Chapter 3 - Storage Media and Devices

Holographic storage

An emerging type of storage technology that uses multiple blue laser beams to store data in three dimensions.

BD-ROM disc

A Blu-ray Disc that can be read from, but not written to, by the user.

CD-ROM disc

A CD that can be read from, but not written to, but the user.

DVD-ROM disc

A DVD that can be read from, but not written to, by the user.

Flash memory

A chip-based storage medium that stores data using electrons; used in a variety of storage systems.

Track

A concentric path on a disk where data is recorded.

Smart card

A credit card-sized piece of plastic containing a chip and other circuitry that can store data.

Optical drive

A drive used with optical discs, such as CD or DVD discs.

Magnetic hard drive

A hard drive consisting of one or more metal magnetic disks permanently sealed, with an access mechanism and read/write heads, inside its drive.

Hybrid hard drive

A hard drive that contains both a large amount of flash memory and magnetic hard disks.

Solid-state drive (SSD)

A hard drive that uses flash memory media instead of metal magnetic hard disks.

Network attached storage (NAS)

A high-performance storage device individually connected to a network to provide storage for computers on that network.

Filename

A name given to a file by the user; it is used to retrieve the file at a later time.

Folders

A named place on a storage medium into which files can be stored to keep the files stored on that medium organized.

Storage area network (SAN)

A network of hard drives or other storage devices that provide storage for another network of computers.

Stored device

A piece of hardware, such as a DVD drive, into which a storage medium is inserted to be read from or written to.

BD-R disc

A recordable Blu-ray Disc

CD-R disc

A recordable CD

BD-RE disc

A rewritable Blu-ray Disc

CD-RW disc

A rewritable CD

Sector

A small piece of a track.

USB flash drive

A small storage device that plugs into a USB port and contains flash memory media.

Flash memory card

A small, rectangular flash memory medium, such as a CompactFlash (CF) or Secure Digital (SD) card; often used with digital cameras and other portable devices.

Storage server

A storage device designed for large computer systems and that typically contains multiple high-speed hard drives.

Remote Storage

A storage device that is not directly connected to the computer being used, such as one accessed through a local network or the Internet.

RAID (redundant arrays of independent disks)

A storage method that uses several hard drives working together, typically to increase performance and/or fault-tolerance.

Optical disc

A type of storage medium bread from and written to using a laser beam.

Storage medium

The part of a storage system where data is stored, such as a DVD disc.

Disk access time

The time it takes to locate and read data from (or position and write data to) a storage medium.

Hard-Disk

is a large capacity storage device housed in the system unit. -Hard disks are divided into Tracks, Sectors, Clusters, Cylinders

Disk cache

Memory used in conjunction with a magnetic hard drive to improve system performance.

Cluster

One or more sectors; the smallest addressable area of a disk.

Sequential access

Sequential access means retrieval of data can occur only in the order in which it was physically stored on the storage medium (Magnetic tape drive)

File

Something stored on a storage medium, such as a program, a document, or an image.

cache memory

Special group of very fast memory chips located on or close to the CPU (Level 1 is fastest, then Level 2, then Level 3,More cache memory typically means faster processing_

Magnetic tape

Storage media consisting of plastic tape with a magnetizable surface that stores data as a series of magnetic spots; typically comes as a cartridge.

Cylinder

The collection of tracks located in the same location on a set of hard disk surfaces.

Partitioning

Divides the physical capacity of a single drive logically into separate areas, called partitions

DVD-R/DVD+R discs

Recordable DVDs

Online storage

Remote storage devices accessed via the Internet; also called cloud storage.

DVD-RW/DVD+RW discs

Rewritable DVDs