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DEIFINITIONS:
STORAGE:
· The act of storing goods or the state of being stored.
· A space for storing goods.
· space or area reserved for storing.
COMPUTER STORAGE:
The process of storing information in a computer memory or on a devices or disk.
TYPES OF STORAGE DEVICES:
There are two types of storage devices in a computer system:
· PRIMARY STORAGE DEVICES
· SECONDARY STORAGE DEVICES
PRIMARY STORAGE DEVICES:
Primary storage devices are also known as main memory or internal memory. It’s a storage location that holds memory for short periods of time. It’s a memory area of computer where current data is stored. This section of the computer is referred to as Random Access Memory (RAM) and consists of volatile memory chips. Data stored temporary on these devices. As the power supply switched off data store on these devices lost.
SECONDARY STORAGE DEVICES:
Secondary storage devices are also known as non-volatile memory. It’s a storage location that holds memory for desired periods of time. It’s a memory area of computer where every type of data cab be stored. Data stored permanently on these devices. As the power supply switched off data store on these devices do not lost like primary storage.
· An optical disc drive (ODD) is a disk drive that uses laser light or electromagnetic waves near the light spectrum as part of the process of reading or writing data to or from optical discs.
· Some drives can only read from discs, but recent drives are commonly both readers and writers.
· Optical disc drives are part of stand-alone computers.
· Optical tape is faster than magnetic tape.
· It has high capacity and high speed to store data.
· It has the capability of storing more than 1 terabyte of data and transfer of data 100 mb per second.
· Compact disc is also known as CD.
· It is used to store digital data.
· Standard CDs have a diameter of 120 mm and can hold up to 80 minutes of uncompressed audio i.e. 720 Megabytes
· It also has many types that are write-once audio and data storage CD-R, rewritable media CD-RW, Video Compact Discs (VCD).
· A CD is made from 1.2 mm thick, almost-pure polycarbonate plastic and weighs 15–20 grams. From the center outward components are at the center (spindle) hole, the first-transition area (clamping ring), the clamping area (stacking ring), the second-transition area (mirror band), the information (data) area, and the rim.
· A thin layer of aluminium or, more rarely, gold is applied to the surface to make it reflective
· There are pits and lands on CD. Data is stored on pits.
· The change in height between pits and lands results in a difference in intensity in the light reflected. By measuring the intensity change with a photodiode, the data can be read from the disc.
· A USB flash drive consists of flash memory data storage device integrated with a USB (Universal Serial Bus). USB flash drives are typically removable and rewritable, much smaller than a floppy disk, and most weigh less than 30 g (1 oz).
· Flash drives use the USB mass storage standard, supported natively by modern operating systems.
· Flash drive consists of a small printed circuit board carrying the circuit elements and a USB connector, insulated electrically and protected inside a plastic, metal, or rubberized case which can be carried in a pocket or on a key chain.
· Computers access modern flash memory systems very much like hard disk drives, where the controller system has full control over where information is actually stored.
· Flash drives can be defragmented, but this brings little advantage as there is no mechanical head that moves from fragment to fragment. Flash drives often have a large internal sector size, so defragmenting means accessing fewer sectors. Defragmenting shortens the life of the drive by making many unnecessary writes.
· Most current PC firmware permits booting from a USB drive, allowing the launch of an operating system from a bootable flash drive. Such a configuration is known as a Live USB.
· WORM stands for Write Once Read Many Times
· it is available in 5.25 inches with 800 mB storage capacity
· Data on WORM cannot be erased.
· WORM stands for Write Once Read Many Times
· it is available in 5.25 inches with 800 mB storage capacity
· Data on WORM cannot be erased.