The document discusses different types of computer memory including primary memory such as RAM and ROM which are used for temporary and permanent storage respectively, secondary memory such as hard disks and optical disks which are used for large scale permanent storage, and cache memory which acts as a fast buffer between the CPU and main memory. It describes the characteristics, uses and examples of each type of memory as well as the differences between memory and storage.

1. Segment 3: Storage/ Memory of a Computer
Computer Fundamentals
Instructor:
M. Furquan Mirza
Final Year, Computer Science and Engineering
International Islamic University Chittagong
mdfurquan183055@gmail.com

2. Contentsoverview
Storage Memory
Storage Vs
Memory
Characteristics
of Memory
Types of
Memory

3. Whatisstorage?
 Storage is a process through which digital data is saved within a
data storage device by means of computing technology.
 Storage is a mechanism that enables a computer to retain data,
either temporarily or permanently.
 Storage may also be referred to as computer data storage or
electronic data storage.

4. Whatismemory?
 Computer memory is just like the human brain.
 It is used to store data/information and instructions.
 It is a data storage unit or a data storage device where data
is to be processed and instructions required for processing
are stored.
 It can store both the input and output can be stored here.

5. MemoryVsstorage
Memory is what our computer uses to store data temporarily,
while storage is where we save files permanently.
When we save a file, it's copied from the memory onto the
storage drive.
Therefore, our computer seems to run slower when it's low on
memory; it must pull data from the storage drive in order to
use it.

6. MemoryVsstorage

7. MemoryVsstorage

8. volatileVsnon-volatile
 The volatile memory stores data and computer programs
that the CPU may need in real-time, and it erases them
once a user switches off the computer.
 Non-volatile memory, on the other hand, is static. It
remains in a computer even after a user switches it off.

9. CharacteristicsofaMemory
 It is faster computer memory as compared to secondary
memory.
 It is semiconductor memories.
 It is usually a volatile memory.
 It is the main memory of the computer.
 A computer system cannot run without primary memory.

10. TypesofMemory
In general, memory is of three types:
1. Primary memory
2. Secondary memory
3. Cache memory

11. TypesofMemory

12. PrimaryMemory
 It is also known as the main memory of
the computer system.
 It is used to store data and programs or
instructions during computer operations.
 It uses semiconductor technology and
hence is commonly called semiconductor
memory.

13. TypesofPrimaryMemory

14. RandomaccessMemory-ram
It is a volatile memory.
Volatile memory stores information based on the power
supply.
If the power supply fails/ interrupted/stopped, all the data &
information on this memory will be lost.
RAM is used for booting up or start the computer.
It temporarily stores programs/ data which has to be
executed by the processor.

15. ram

16. Typesofram
 SRAM (Static RAM): It uses transistors, and the circuits of this
memory are capable of retaining their state as long as the power is
applied. This memory consists of the number of flip flops with each
flip flop storing 1 bit. It has less access time and hence, it is faster.
 DRAM (Dynamic RAM): It uses capacitors and transistors and
stores the data as a charge on the capacitors. They contain
thousands of memory cells. It needs refreshing of charge on
capacitor after a few milliseconds. This memory is slower than
SRAM.

17. Readonlymemory-rom
 It is a non-volatile memory.
 Non-volatile memory stores information even when there is a
power supply failed/ interrupted/stopped.
 ROM is used to store information that is used to operate the
system.
 The information stored in the ROM in binary format.
 It is also known as permanent memory.

18. Typesofrom

19. Typesofrom
 MROM(Masked ROM): Hard-wired devices with a pre-
programmed collection of data or instructions were the first
ROMs.
 PROM (Programmable Read Only Memory): The user
purchases a blank PROM and uses a PROM program to put the
required contents into the PROM.
 EPROM (Erasable Programmable Read Only Memory): It is
an extension to PROM where you can erase the content of ROM.
 EEPROM (Electrically Erasable Programmable Read Only
Memory): Here the written contents can be erased electrically.

20. rom

21. Secondarymemory
 It is also known as auxiliary memory and backup memory.
 It is a non-volatile memory and used to store a large amount of
data or information.
 The data or information stored in secondary memory is
permanent, and it is slower than primary memory.
 A CPU cannot access secondary memory directly.
 The data/information from the auxiliary memory is first
transferred to the main memory, and then the CPU can access it.

22. TypesofSecondarymemory
1.Magnetic Tapes 2. Magnetic Disk

23. TypesofSecondarymemory
3. Optical Disks
1. CD ROM
Compact Disk- Read Only Memory
2. Write Once Read Memory (WORM)
3. Digital Versatile Discs

24. cachememory
 It is a type of high-speed semiconductor memory that
can help the CPU run faster.
 Between the CPU and the main memory, it serves as a
buffer.
 It is used to store the data and programs that the CPU
uses the most frequently.

25. cachememory

26. cachememory

27. Basicarchitectureofmemory

28. Referenceanddisclaimer
 Computer Fundamentals: Dr. Mohammad Lutfor Rahman
 Computer Fundamentals Tutorial - W3schools
 Computer Fundamentals Tutorial - Tutorialspoint
 Learn Computer Fundamentals Tutorial – Javatpoint
 Computer Memory - GeeksforGeeks