The Structure of a Computer - English

The Structure of a Computer

The main  structural elements associated with a computer system are as follows:

1. Central Processing Unit (CPU) - data processing and control
2. Main Memory (primary storage) - stores data
3. Secondary Storage - stores permanent data
4. Input and Output (I/O) devices - moves data between the computer and its external environment
5. System interconnection - provides mechanism for communication among various components

The two components at the heart of the hardware structure are the central processing unit (CPU) and the main Memory. The CPU monitors and controls the operation of the other devices and the flow of information to and from these devices, and it performs all the necessary manipulations of the data. 

The Main Memory is used to store information for immediate access by the CPU. Main Memory is also referred to as Primary Storage or Main Store. Secondary storage devices provide permanent storage of large amounts of data. Secondary storage is also called: secondary memory, external memory, backing store or auxiliary storage. This storage may consist of magnetic tapes, magnetic disk, optical memory device, or similar device.

Input/output devices provide an interface between the computer and the user. There is at least one input device (e.g. keyboard, mouse, measuring device such as a temperature sensor) and at least one output device (e.g. printer, screen, control device such as an actuator). Input and output devices like keyboards and printers, together with the external storage devices, are referred to as peripherals

The computer system requires interconnections between the various components. When these data paths carry more than one bit simultaneously from a number of different components, it is referred to as a data bus or simply Bus.