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Some differences between RAM and ROM are as follows:
RAM ROM
Data is lost when the power is turned off. Data remains intact even when the power is off.
Data can be easily changed, added, or deleted. Data cannot be modified or erased easily.
Secondary Memory
Secondary storage refers to external storage devices that retain data permanently, even when
the computer is powered off. They have larger storage capacities compared to primary storage.
You can save your important files, pictures, and games on secondary storage, and they will stay
there until you decide to delete them. Some of the commonly used secondary storage devices
are as follows:
Hard Disk Drive (HDD): A hard drive or hard disk drive (HDD) is a traditional
storage device that is used in laptops and desktop computers. It uses
magnetic disks (also called platters) to read and write data.
Solid State Disk (SSD): A Solid-State Drive (SSD) is a type of
storage device that uses flash memory to store data. As
compared to HDD, SSDs have no mechanical components,
making them faster, more durable, and less prone to failure.
Compact Disc (CDs): It is a small, round storage medium used to store data.
There are different types of CDs, such as CD-ROM (for data), CD-R (recordable),
and CD-RW (rewritable), allowing users to write or erase data.
USB Flash Drive: It is a small, portable storage device used to
store and transfer data. It connects to computers, laptops, or other devices
using a USB (Universal Serial Bus) port. They come in different sizes, ranging
from a few gigabytes (GB) to hundreds of GBs.
Cloud Storage: It is a type of storage that allows you to save data, like files,
photos, and videos, on the Internet instead of using any physical devices like hard
drives or USB flash drives. With cloud storage, you can access your data from any
device (phone, tablet, or computer) as long as you have an Internet connection.
This means you don’t need to carry a physical storage device. Examples of Cloud Storage are
Google Drive, Dropbox, Microsoft OneDrive, and iCloud.
Boost Bits
A bit is the basic unit of memory and represents either a 0 or a 1 in binary code.
MEASURING UNIT FOR MEMORY
The measuring unit helps us understand how much space is available or used in storage devices
like hard drives, USB flash drives, or cloud storage. Just like we measure distance in meters or
weight in kilograms, memory is measured in bytes.
Fundamentals of Computer 17

