1.1 Categorize storage devices and backup media


Floppy Connection

Floppy Connection on Motherboard

Floppy Drive

Floppy Drive


(floppy disk drive) has only 1.4 Mb storage space. Was used for backup of data and mode of transferring data from one PC to another. As of 2005 3½-inch drives were still common equipment on many new PCs other than laptops. But have become pretty much obsolete, portable storage options, such as USB storage devices and recordable or rewritable CDs / DVDs have taken its place.


(hard disk drive) A device containing one or more inflexible platters coated with material in which data can be recorded magnetically, together with their read/write heads, the head-positioning mechanism, and the spindle motor in a sealed case that protects against outside contaminants. The protected environment allows the head to fly 10 to 25 millionths of an inch above the surface of a platter rotating typically at 3600 to 7200 rpm; therefore, much more data can be stored and accessed much more quickly than on a floppy disk. Most hard disks contain from two to eight platters.

Solid state vs. magnetic

Solid state disk drive, a mass storage device that holds data in RAM rather than in magnetic storage.

Magnetic disk, a computer disk enclosed in a protective case (hard disk) or jacket (floppy disk) and coated with a magnetic material that enables data to be stored in the form of changes in magnetic polarity (with one polarity representing a binary 1 and the other a 0) on many small sections (magnetic domains) of the disk surface. Magnetic disks should be protected from exposure to sources of magnetism, which can damage or destroy the information they hold.

Optical drives

CD-ROM Compact Disc Read-Only Memory Used for data storage and data transfer. A standard 120mm CD-ROM holds 650 or 700 Mb of data.

DVD-ROM Digital Versatile Disc or Digital Video Disc is an optical disc storage media format that can be used for data storage, including movies with high quality video and sound. DVDs resemble compact discs as their physical dimensions are the same but they are encoded in a different format and at a much higher density allowing for a greater data capacity of about 4.7 GB


  • CD-RW recorder can rewrite 700 MB of data to a CD-RW disc roughly 1000 times.
  • CD-RW recorders can also write CD-R discs. Except for the ability to completely erase a disc, CD-RWs act very much like CD-Rs.
  • CD-RWs cannot be read in CD-ROM drives built prior to 1997.
  • CD-R is considered a better technology for archival purposes as disc contents cannot be modified.


  • Rewritable optical disc with equal storage capacity to a DVD-R, typically 4.7 GB.
  • Primary advantage of DVD-RW over DVD-R is the ability to erase and rewrite to a DVD-RW disc.
  • DVD-RW discs may be written to about 1,000 times before needing replacement, making them comparable with the CD-RW standard.
  • DVD-RW discs are commonly used for volatile data, such as backups or collections of files.

Dual Layer recording allows DVD-R and DVD+R discs to store significantly more data, up to 8.5 Gigabytes per disc, compared with 4.7 Gigabytes for single-layer discs


Is an optical disc storage medium designed to supersede the standard DVD format. Its main uses are for storing high-definition video, and other data, with up to 25 GB per single layered, and 50 GB per dual layered disc. The disc has the same physical dimensions as standard DVDs and CDs.

The name Blu-ray Disc derives from the blue-violet laser used to read the disc. While a standard DVD uses a 650 nanometer red laser, Blu-ray uses a shorter wavelength, a 405 nm blue-violet laser, and allows for almost six times more data storage than a DVD.

Removable storage

Tape drives mainly for backup and long-term storage. Can be connected with SCSI (most common), parallel port, IDE, USB, FireWire or optical fibre. Tape drives can range in capacity from a few megabytes to upwards of 800 GB compressed.

External CD-RW and hard drive May be used for backup, easy transfer of data to another PC, and are good choices for offsite backup data storage in case of fire et..

Thumb drive, flash and SD cards small, lightweight, removable and rewritable data storage devices. Some recent USB flash drives act as two drives - as a removable disk device , and as a USB floppy drive. This is likely intended to make it easier to use them as a bootable device.

Hot swappable devices and non-hot swappable devices

Hot swapping and hot plugging are terms used to separately describe the functions of replacing system components without shutting down the system. Hot swapping describes changing components without significant interruption to the system, while hot plugging describes changing or adding components which interact with the operating system. Both terms describe the ability to remove and replace components of a computer, while it is operating. For hot swapping once the appropriate software is installed on the computer, a user can plug and unplug the component without rebooting. A well-known example of this functionality is the Universal Serial Bus (USB) that allows users to add or remove peripheral components such as a thumb drive, external hard drive, mouse, keyboard, or printer.