Question

1)Difference between RAM &ROM
2)What is volatile and non- volatile?

Answer 1

RAM
random access memory
volatile memory

volatile memory is type of memory where it can be erased when the system is off


ROM
read only memory
non volatile memory

non volatile memory is type of memory which doesnot get erased when the system is off

Answer 2

RAM means RANDOM ACCESS MEMORY
ROM means READ ONLY MEMORY
Difference-
RAM is the memory available for the operating system, programs and processes to use when the computer is running.  
ROM is the memory that comes with your computer that is pre-written to hold the instructions for booting-up the computer.

RAM requires a flow of electricity to retain data (e.g. the computer powered on).
ROM will retain data without the flow of electricity (e.g. when computer is powered off).

RAM is a type of volatile memory. Data in RAM is not permanently written. When you power off your computer the data stored in RAM is deleted. 
ROM is a type of non- volatile memory. Data in ROM is permanently written and is not erased when you power off your computer.

Hope it was helpful:-)