Examples of Backing – Storage Media

What is Secondary Memory / Backing storage?

Secondary memory is an additional memory used to hold large amounts of information outside the main memory. A microcomputer is more useful if it has some backing memory.

A secondary storage device is also known as an auxiliary storage device, backup storage device, tier 2 storage, or external storage.

These are used to hold numbers, characters, and information as opposed to cassette tapes which hold music.

Let’s discuss these various types of storage media:

The Hard Disk:

The hard disk is in the form of a round metallic plate, that is mounted on a spindle inside the System Unit. It is also called the fixed disk because once it is installed; it remains in the system unit unless it is damaged.

However, modern technology has now developed a removable hard disk. This allows for the security of data where sensitive data are stored.

A hard disk holds more information than a floppy disk. It can also collect information more rapidly from the CPU, than the floppy disk. The hard disk capacity is measured in MB (Megabyte) or GB (Gigabyte)

New innovations have come up with terms such as Terabyte (billions of bytes) Zettabyte (Trillions of bytes)

The hard disk drive is the primary storage location where data is permanently stored.

The Magnetic Tape:

This is a thin strip of plastic coated with a magnetic recording material, that is normally held in a plastic-coated case. It is used principally as a backup storage medium. It is not used for secondary storage, because of the relatively long access time it takes, to retrieve data that is a long way into the tape. Data is held sequentially on the tape, and since the tape is held on reels, the last data to be saved to the tape is at the end of the reel.

The Magnetic Disk:

This is a secondary storage device, that consists of a plastic disk coated with magnetically sensitive material. Magnetic disks are usually described as floppy disks or hard disks depending on their construction. Hard disks generally have a higher storage capacity.

CD (Compact Disk) CD-ROM:

CD-ROM (Compact Disc Read-Only Memory) is a type of compact disc that can only be read, not written to. Compact disk (CD) is a system invented by Phillips in 1983.

CD-ROM can store a much larger amount of data than conventional storage. Although slower than hard disks, a CD-ROM will store in excess of 600 MB of data. They are very useful for the storage of archival data. Video and sound can also be stored on a CD, making possible multimedia applications.

Zip Disk:

ZIP disk is a popular magnetic storage that allows 100 MB of data. It is used primarily as a backup. The content of the ZIP disk is read by a computer, through a ZIP drive. The Zip disk and Zip drives come in two sizes. The 100 MB size actually holds up to what 70 floppy diskettes can contain. There is also a 250-megabyte drive and disk.

USB Flash Drives/Disks:

This is a key-sized computer storage device, with a storage capacity of 1 to 8 GB. USB stands for Universal Serial Bus. It supports a data transfer rate of 12 Mbps and can be put into a pocket, or attached to a key holder. It is also found to be resistant to scratches, dust, breaks, or mechanical failure.

USB is a removable storage media that utilizes solid-state RAM, to store information for a long period of time. Solid State RAM technology, is also used in memory cards for digital cameras and media players. SSD (Solid State Drives) have a faster access speed, than the hard disk and have no moving parts.

Floppy Disk (Diskette)

This is another secondary storage device. The floppy disk is a plastic disk. Information is stored on both surfaces of the disk. The disk is sealed inside a jacket as a protective coat in a square shape.

A floppy disk is removable and can be inserted in the drive apartment of the computer. Types of floppy disks include:

• 8-inch floppy
• 5¼ inch floppy disk (Mini floppy)
• 3½ inch floppy disk (Micro floppy)

The diskettes can either be single-sided (SS) or double-sided (DS)This means that data can be stored on one side or on both sides respectively.

High-density double-sided floppy disks could store 1.44 MB of data.

The Floppy Disk Has Become Obsoleteno longer produced or used; out of date. More / Out-of-date And Old Fashioned.

In recent times, it is not as common for computers to be manufactured with floppy disk drives. Before now, they were used primarily for backing storage on small computers. They were also media through which we supplied software for use on a microcomputer. We used to collect data for subsequent transfer, to another system using the floppy disk. They were also used to back up important information from the hard disk and save scanned pictures.