RAM is the most common type of computer memory. It is volatile, meaning stored information is lost when power is removed. RAM is made up of small memory chips that form modules to store operating systems, programs and data for quick access by the processor. RAM was invented in 1968 and its capacity has doubled approximately every two years. Common RAM types are SRAM and DRAM. RAM provides faster access than storage drives but requires constant power to maintain data.

1. RAM (Random Access Memory)
Md. Rafiul Islam
PGD-0906

2. Index:
• Introduction
• History
• Technologies
• Position & Structure
• Types of Ram
• Memory cell
• Difference
• Capacity to store
• Manufacturing companies
• Other uses of RAM
• Advantage & Disadvantage

3. Introduction:
• Random access memory (RAM) is the best known form of computer
memory.
• RAM is considered as volatile memory, which means that the stored
information is lost when there is no power.
• RAM is made up of small memory chips that form a memory module.
• Whenever you open a program, it gets loaded from the hard drive
into the RAM.
• This is because reading data from the RAM is much faster than
reading data from the hard drive.

4. What is RAM(Random access memory)?
RAM (Random Access Memory) is the hardware in a computing device
where the operating system (OS), application programs and data in
current use are kept so they can be quickly reached by the device's
processor. RAM is the main memory in a computer, and it is much
faster to read from and write to than other kinds of storage, such as a
hard disk drive (HDD), solid-state drive (SSD) or optical drive.

5. History:
• RAM (Random Access Memory) was invented by Robert Heath
Dennard at IBM Thomas J Watson Research Center in 1968.

6. Technologies Of Ram:
Type Year
Fpm (Fast page mode) 1990
EDO (Extended data o/p) 1994
SDRAM (Single dynamic RAM) 1996
RDRAM 1998
DDR SDRAM 2000
DDR2 SDRAM 2003
DDR3 SDRAM 2007
DDR4 SDRAM 2012

7. Position Of Ram:

8. Structure of Ram:
Notches for socket
”Handles”
Socket Edge connector

9. Types Of Ram:
• SRAM (Static Random Access Memory)
• DRAM (Dynamic Random Access Memory)
SRAM (Static Random Access Memory)
oSRAM holds data in a static form, as long as the memory has power.
oEach bit is stored on four transistor that forms two cross coupled inverters.
DRAM (Dynamic Random Access Memory)
oDRAM is called dynamic because it must constantly be refreshed and lose
the data in very short time.
oDRAM stores each bit of data in a separate capacitor within a integrated
circuit.

10. Memory cell:
SRAM Cell (6 Transistors) DRAM Cell (1 Transistor and one capacitor)

11. Difference:
SRAM DRAM
• Requires less memory. • Requires more memory.
• Access time is low. • Access time is more.
• Do not refresh. • Needs to be refreshed.
• Faster access time. • Slower access time.
• More power consumption. • Less power consumption.
• Used in cache memory. • Used in main memory

12. Capacity Of Ram:
From Beginning:
• 256 MB
• 512 MB
• 1024 MB (1 GB)
• 2048 MB (2 GB)
• 4096 MB (4 GB)
• 8192 MB (8 GB)
• NOTE: Here every time the size of Ram increased by multiplying twice.

13. Manufacturing companies:
• ASUS
• Buffalo Technology
• Century
• CEON
• CHAINTECH
• ELIXIR
• HP
• IBM

14. Other uses of RAM:
In addition to serving as temporary storage and working space for the
operating system and applications, RAM is used in numerous other
ways.
• Virtual memory
• RAM disk
• Shadow RAM

15. Advantage & Disadvantage:
Advantage:
• Programs will load much faster.
• Power Efficient, that uses much less power than disk drives.
Disadvantage:
• Volatile: a power outage will cause irrecoverable data loss.
• Space-limited: cost per bit is high.

16. The end
Thanks to all.