This document discusses different types of computer memory. It describes primary memory, which includes RAM that temporarily stores the operating system, and ROM with instructions from the manufacturer. RAM is volatile while ROM is read-only. ROM types are PROM and EPROM. Secondary memory includes hard disks for long-term storage, as well as external hard disks and CDs, which allow storing large amounts of data beyond what primary memory can hold. Secondary storage devices are used to save files when the computer is turned off.

1. MEMORY BITS AND
BYTES
BY MIHIT AND KRISHNA

2. COMPUTER MEMORY
• The memory of computer is of
two types: Primary memory and
Secondary memory.

3. PRIMARY MEMORY
Primary memory, also known as
the internal memory or main
memory of the computer, is the
hardware component that the
computer uses for its internal
function.

4. RAM
• Ram stands for Random Access
Memory (RAM). When a
computer starts the operating
system is loaded onto the ram.

5. ROM
• Rom stands for Read Only
Memory. Rom is that part of the
computer memory which
comprises instructions burnt by
the manufacturer to run the
computer.

6. TYPES OF ROM
(PROM EPROM)
• ROM can be of two different
types:

7. PROM
• This stands for Programmable
read only memory. Prom
programmer can write
information into it using some
special equipment.

8. EPROM
• It stands for erasable
programmable read only
memory. It is non-volatile and
once programmed, it can be
erased exposing to strong
ultraviolet light source and high
voltage electric pulses.

9. Secondary memory
• You know that computer can store a
large amount of data. However, the
primary memory stores only a limited
amount of data and/or is volatile.

10. TYPES OF SECONDARY
STORAGE DEVICES
• There are different types of
secondary storage devices.
Some of the commonly used
ones are discussed here.

11. HARD DISK
• The hard disk is a magnetic disk
with huge storage capacity. While
working on computer, when you
click on the save button, your file or
folder gets saved on the hard disk of
the computer.

12. EXTERNAL HARD DISK
• These days there can be more than
one hard disk in computer. Additional
hard disk can be attached externally
and carried anywhere like an external
device.

13. CD’s
• CD stands for compact disc. It is a circular
disc with a shiny surface on one side. It can
store up to 700 MB of data. The data is
stored on its shiny surface.