COMPUTER MEMORY

1. COMPUTER
MEMORY
PRESENTATION BY
NIKUNJ PATEL

2. HISTORY
OF
MEMORY

3. HISTORY OF MEMORY
 In the early 1940s, memory technology mostly
permitted a capacity of a few bytes.
 ENIAC(Electronic Numerical Integrator And
Computer): Firs electronic general-
purpose computer .
 That is capable of being reprogrammed to
solve a large class of numerical problems.

4. DELAY
LINE
MEMORY

5. DELAY LINE MEMORY
 developed by J. Presper Eckert in the early
1940s.
 It is also used in digital computers.
 Delay line memory would be limited to a
capacity of up to a few hundred thousand bits to
remain efficient.

6. RANDOM ACCESS
COMPUTER MEMORY

7. RANDOM ACCESS
COMPUTER MEMORY
 The Williams tube and Selectron tube originated
in 1946.
 In 1947 Jay Forrester, Jan A. Rajchman and An
Wang developed magnetic core memory which
allowed for recall of memory after power loss.
 The Selectron was limited to 256 bits, while the
Williams tube could store thousands

8. RANDOM ACCESS
COMPUTER MEMORY

9. MAGNETIC
CORE
MEMORY

10. MAGNETIC CORE MEMORY
 It was the
computer
memory of
choice
throughout the
1960s, until it
was replaced
by
semiconductor
memory.

11. MEMORY

12. MEMORY
 It holds the data and instructions that the
Central Processing Unit (CPU) needs.
 Before a program can be run the program is
loaded from the storage medium into memory.
 It allows the CPU to direct interact with the
program.
 Memory is a need of every computer

13. TYPES OF MEMORY

14. TYPES OF MEMORY
 ROM (Read Only Memory)
 RAM (Random Access Memory)
 Cache memory
 Flash memory

15. READ ONLY MEMORY
 stores data
without electrical
current; it is the ROM
(Read Only Memory)
 or is sometimes
called non-volatile
memory as it is not
erased when the
system is switched off

16. RAM
 Random Access Memory, can be accessed
randomly. Any byte of memory can be accessed
without touching the preceding bytes. RAM is the
most common type of memory found in computers
and other devices, such as printers.

17. DDR2 RAM & DDR3 RAM

18. TYPES
OF
RAM

19. TYPES OF RAM
 There are two different types of RAM:
DRAM (Dynamic Random Access
Memory)
SRAM (Static Random Access
Memory).

20. DRAM
 Needs to be refreshed thousands of times per
second while.
 Dynamic RAM needs to automatically refresh
thousands of times per second; that's where it gets
the name dynamic. Otherwise, it will forget the
information it's holding.

21. SRAM
 Does not
need to be
refreshed, which is
what makes it
faster than DRAM.
 Both types of
RAM are volatile,
meaning that
they lose their
contents when
the power is
turned off.

22. CACHE MEMORY

23. CACHE MEMORY
 The cache is
a smaller, faster
memory which
stores copies of
the data from
frequently
used main
memory locatio
ns.

24. FLASH MEMORY

25. FLASH MEMORY
 Non volatile memory can be erased
electronically and rewritten similar to EEPROM.
 Introduced by Toshiba in 1984.
 Most computers use it to hold up their startup
instructions.
 Also used in many mobiles , smart phones ,
digital cameras and PDA.

26. FLASH MEMORY

27. THANK
YOU