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Random Access Memory (RAM)
RAM is a temporary memory. The information stored in this
memory is lost when the computer is turned off. That’s why it is also
called volatile memory. It temporarily stores data and instructions
given by the user and also the results produced by the computer.
Types of RAM: RAM
1. Dynamic RAM (DRAM): It requires continuous power to refresh the data stored.
2. Static RAM (SRAM): It also requires constant power to hold on to data, but it doesn’t
need to be continually refreshed the way DRAM does.
However, SRAM is significantly faster and uses less power than DRAM.
Read Only Memory (ROM)
Information stored in ROM is permanent in nature, 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
ROM
non-volatile memory.
Secondary Memory
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. It is cheaper as compared to primary memory.
Secondary memory devices are also called secondary storage devices. They are categorised
into three types: Magnetic disk, Optical disc and Flash drive.
Secondary Storage Devices
Magnetic Disk Optical Disc Flash Drive
Hard Disk CD DVD Blu-Ray Disc Pen Drive Memory Card
Magnetic Disk
A device, covered with a magnetic coating is called a magnetic disk. You can record and
erase data on a magnetic disk any number of times.
Hard Disk
The hard disk consists of one or more magnetic disks. Each
disk in the pack has top and bottom surfaces on which data is
recorded using magnetic head. It is permanently fixed in the
system unit. The most important function of the hard disk is to
store program files and data files. Hard disk
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iPlus (Ver. 2.0)-IV

