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RAM (Random Access Memory)
It is temporary in nature. The computer holds information in this memory and gets it
when needed. It remembers what you tell them and can even change to remember
new information. It is volatile in nature, which means that data will be erased when the
computer is turned off. That’s why you always save your work! RAM is considered “random Random Access Memory
access” because any part of it can be accessed randomly for reading or writing of the data.
ROM (Read Only Memory)
It is permanent in nature. It is non-volatile which means its contents remain even after the
computer is turned off. The information is coded at the time of manufacturing the computer.
Read Only Memory The computer needs this information for its basic functions.
Secondary Memory
Secondary Memory provides extra storage where the data can be stored permanently for later use. It is also known
as external memory as it can be stored anywhere. Examples of secondary memory are compact disc, hard disc,
flash drive, etc.
Hard Disk
A Hard Disk stores and provides quick access to large amounts of data on an electromagnetically
charged surface or set of surfaces. Hard disks are generally fitted inside the system unit. However,
there are external hard disks also available. A hard disk is made-up of a collection of disks called
platters stacked on a cylindrical rod. Each of which, like phonograph records, has data recorded
electromagnetically in concentric circles or “tracks” on the disk. The capacity of a hard disk varies Hard Disk
from a few Gigabytes to a few hundred Terabytes.
CD
A compact disc is a small, portable, round disc made of molded polymer used for recording, storing,
and playing back audio, video, text, and other information in the digital form. It was originally
developed to store sound recordings exclusively, but later it also allowed the preservation of other
CD types of data. It stores data of low capacity upto 700 MB.
DVD
Digital Versatile Disk is used for storing digital data using optical rays. It is the same size as a CD, but
has a larger storage capacity. They are commonly used to store large volumes of data including audio
and video files. It stores data upto 10 GB.
DVD
Blu-ray Disc
Blu-ray disc is of the same dimension as that of CD or DVD and uses the same optical rays technology
for recording and playing back high-definition (HD) video and for storing large amounts of data. It
has a capacity of up to 25 GB.
Blu-ray Disc
Flash Memory
Flash drive functions as a portable hard drive. It’s a small and portable memory card that plugs into
a computer’s USB port. USB flash drives are smaller and more durable with large storage capacity.
It can be used in any computer with USB port. USB flash drives are also called thumb drives, pen
drives, key drives, or simply USB drives. It stores data upto 2 TB. Flash Drive
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