RAM

Memory
To store information given to the system we need some space known as storage /memory

of the system.
Any computer knows only(1,0)binary code.
The binary code have a unique sequence for all given information to the system.
We generally used "WRITE"word for storing data in the system & word "READ" represent for collect/carry/fetching of data.
**"Byte" is the unit of the memory.
**"Bit" is the smallest unit of the memory.
                    ⇛8 bit = 1 Byte

RAM

random access memory-
It is a primary or main memory.
It is used for collecting the information and process to it with the help of C.P.U [ CENTRAL PROCESSING UNIT ] & processor. But it can't be hold data permanently.
It loose data if the power cut take place in teh system.So it is also known as "Volatile" memory.
There are 2 type of RAM 

Dynamic RAM :
This is the type of Random access memory which constantly need to be refreshed.this is little-bit slow.

• DDR
• DDR2
• DDR3 .

Where DDR means -- Double Data Rate. It represent for the -" How much data can be transfer in one clock cycle.

Static RAM :

This is an another type of the Random access memory which does not required and refreshment.This type of RAM is generally very fast in comparison with dynamic RAM. *But both are the volatile memory-(they loose their content if the system does power off.

Thanks!