primary and secondary memory
PRIMARY MEMORYThere are 2 types of memory which and primary and secondary memory. Primary memory is physically made up of Random Access Memory (RAM) which is also known as "volatile memory". Software which is being processed by the CPU (Central Processing Unit), otherwise known as 'executing software', is stored in the main memory for a short period of time. Normally a computer will have between 1 - 4 Gigabytes of RAM outside the main CPU. The CPU itself will also contain volatile memory in the form of registers and cache.
secondary memorySecondary memory, or secondary storage, is non-volatile storage. Examples of this are flash drives, hard disk drives, etc. Secondary memory is used to hold data and programs which are not currently being used, but need to be accessed at some point.
Normally a personal computer will have a few hundred gigabytes of secondary memory in the form of a hard disk. PRIMARY VS SECONDARYPrimary memory is directly accessed through CPU. The accessing of the primary memory through CPU is done by making use of address and data buses, whereas input/ output channels are used to access the secondary memory. Also, secondary memory is not directly accessed by the CPU.
The primary memory is embedded with two types of memory technologies; they are the RAM (Random Access Memory) and ROM (Read Only Memory). The secondary memory is accessible in the form of Mass storage devices such as hard disk, memory chips, Pen drive, floppy disk storage media, CD and DVD. Primary memory is volatile in nature, while secondary memory is non volatile. The information that is stored in the primary memory will not be kept when the computer has been shut down. In case of secondary memory, the information can be retrieved even if the power is turned off because the data will not be erased unless the person deletes it themselves. |