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Read Only Memory (ROM)
ROM is the permanent memory, i.e., it holds the data even if the system
is switched off. It holds the starting instructions that are required to
start a computer. It is also called non-volatile memory.
Secondary Memory ROM DVD
This memory is permanent in nature and is not directly accessed by the CPU. It allows users to
store data that may be easily retrieved.
Secondary memory devices are also called secondary storage devices. Lets learn about some
secondary storage devices.
Hard Disk
Hard disk is permanently fixed in the CPU Box. The most important
function of the hard disk is to store program files and data files.
Hard disk
Factbot
World's first hard disk was introduced by IBM in 1956.
Hard disks are available in a variety of sizes with storage
capacities as high as 5 TB (Terabyte) or even more. The CPU can
access data stored on a hard disk much faster than it can access
data on a CD.
External hard disks are also available. They are the hard disks that External hard disk
can be connected to any computer with the help of a USB port.
Compact Disc (CD)
Compact disc (CD) is an external storage device. It can hold upto 700 MB
of data. To be able to write data on or read data from a CD, you need a
component called a CD drive. The CD drive reads information stored on a
compact disc. CD drive is usually connected inside the CPU box but can CD
also be connected using a USB port.
CD Drive
12 Plus (Ver. 4.0)-IV

