Difference between primary memory and secondary memory

Primary memory	Secondary memory
1.It is known as main memory.	1.It is known as backup memory.
2.These are semiconductor memories.	2.These are magnetic and optical memories.
3.It is usually volatile memory.	3.It is non-volatile memory.
4.In this type of memory,data is lost in case power is switched off.	4.In this type of memory,data is permanently stored even if power is switched off.
5.It is working memory of the computer.	5.It is used for storage of data in a computer.
6.A computer cannot run without primary memory.	6.Computer may run without secondary memory.
7.It is faster than secondary memory.	7.It is slower than primary memory.