2.1 Memory

Memory is a unit place where data or information is stored for some time period. Some memory can store data for temporary period while others can store for permanent time period. Similarly some memory require power backup to hold data while others do not require power backup. Small size to large size data holding memories are used in computer. The storage capacity of memory is measured in Byte. 1 Byte = 8 Bit

Depending on memory usage, memory is classified into two types:-

Primary Memory:

Primary memory refers to RAM and ROM, which are necessary to boot (Run) computer for the first time. When computer is switched ON for first time the data from ROM is loaded to RAM sends data to processor which helps to start computer and data is displayed on monitor. Later operating system data is loaded and then only user can access computer. 

Primary memories are small size memories which requires power backup to hold data and are most essential to run computer system.

Secondary Memory:

These memories used in computer system which can store large amount of data or information for permanent time period without need of power backup are secondary memory. Secondary memory are not essential to boot for the first time when computer is switched ON. Since they are used to store operating system files and other data or information for further use, they are called auxiliary memory.

Example: Hard Disk, Floppy Disk, CD, DVD, Pendrive etc.