Difference between ram and rom

Read-Only Memory (ROM) is a storage area that is used to store instructions. The contents of read-only memory are permanent. That means, switching off the power supply will not erase the data stored in ROM. The data stored in ROM is either unchangeable or requires special operations to change the contents. A normal user cannot write anything in read-only memory.
Random Access Memory (RAM) also called the main memory of the computer, is a storage area that acts as a rough working area for the programs It is a read-write memory. That means a user can read the contents stored in it as well as he writes the contents on to the memory. RAM temporary storage area that means, the con cannot be permanently stored in random a memory. The contents of random access to me are lost when the computer is switched off. That is why it is also called "volatile memory".