Different memories are used by computer for storing data. These are following. RAM It is known as random access memory. It is non volatile memory. Once the data is stored cannot be changed by user or any one else. When computer is shut down all the memory is lost and cannot be retrived back.
ROM It is read only memory. It is volatile memory. When the computer is shut down memory is not lost by the computer. It is also called permanent memory. There are kind of ROM. In Erasable read only memory the data can be erased. In Electronically eraseable memory the data is erased with the help of electronically.
Floppy disk. It is a thin disk covering with black plastic material. The data is stored in floppy. Megnatic disk. In it the data is stored in it. It has a plastic tape where data is stored. CD. Cd is widely used storing device. The components are made on disk where data is stored. The storage capacity of cd is high.