memory in computer

1. Submitted by
BBA 1st

2. INTRODUCTION
In computing memory refers to the
physical devices used to store programs
(sequences of instructions) or data (e.g.
program state information) on a temporary
or permanent basis for use in a computer or
other digital electronic device.

4. TYPES OF MEMORIES

5. PRIMARY OR MAIN MEMORY
 Main memory is divided into two parts :
Random Access memory (RAM), should be better
known as Read Write Memory (RWM).
Read Only Memory (ROM) .

6. RANDOM ACCESS MEMORY
(RAM)
 A RAM memory chip is an integrated circuit (IC)
made of millions of transistors and capacitors. In
the most common form of computer memory,
dynamic random access memory (DRAM), a
transistor and a capacitor are combines to create a
memory cell, which represents a single bit of data.

7. TYPES OF RAM
 STATIC RAM
Semi conductor memory
Uses flip flop to store each bit of memory so does not
need to be periodically refreshed
Fast and consumes low power
Expensive and has complex structure(6 transistors) so
not used for high capacity applications

8.  DYNAMIC RAM
Stores each bit of memory in capacitor in an intrgrated
circuit
Real capacitors leak charge so capacitors need to be
refreshed periodically
Simple structure (1 capacitor and 1 transistor per bit)
so it has very high density

9. D RAM

10. READ ONLY MEMORY
(ROM)
 New contents cannot be added
 Used to store the instructions of routine
type,permanent in nature and used to control or
supervise the hardware

11. Read only memory (ROM)

12. TYPES OF ROM
 PROGRAMMABLE READ ONLY MEMORY
(PROM)
Programmed to record the information using a
facility PROM – programmmer
Once the information is recorded it cannot be
changed

13. TYPES OF ROM

14.  ERASABLE PROGRAMMABLE READ ONLY MEMORY
(EPROM)
Information can be erased and chip can be reprogrammed
to record different information using PROM programmer
In formation is erased using UV radiations
It is of two types- Ultra Voilet Erasable Programmable
Read Only Memory (UEPROM) and Electrically Alterable
Programmable Read Only Memory (EAPROM)

15.  ELECTRICALLY ERASABLE
PROGRAMMABLE READ
ONLY MEMORY
(EEPROM)
 Memory is erased by
electrical signals
 Provides easy means to
store temporary or
permanent information in
the form of ROM memory

16. Types of Rom

17. CACHE MEMORY
Faster and expensive than RAM
It improves the computer’s performance and is less
than 512 KB
Processor can use it to store frequently accessed data
and programs instructions
It is of two types – L1 / primary cache(inside
microprocessor) and L2/ secondary cache(in the
mother board or near the microprocessor)

18. CACHE MEMORY

19. SECONDARY MEMORY
 It supplements the main memory. It is permanent
memory.
 Programs, data entered into the system,
intermediate results and final results produced are
stored in the secondary memory

20. SECONDARY MEMORY

21. CLASSIFICATION
 MAGNETIC BASED
STORAGE DEVICES
 Prepared using using
formatting
 Data is recorded on
disk in concentric
circular bands called
tracks.
MAGNETIC TAPE
FLOPPY DISK
HARD DISK

22.  OPTICAL STORAGE MEDIA
Stores large amount of data in some formats as
much as the entire hard disk
Reads data by focusing a laser- generated beam of
light on light on disc’s surface
 CD- ROM discs
 DVD- ROM discs

24. MEMORY HIERARCHY
Ranking of computer
memory devices, with
devices having the
fastest access time at
the top of hierarchy,
and devices with slower
access time but larger
capacity and lower cost
at lower levels

25. Thanx I Hope You
Like This