29-07-2011, 04:34 PM
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Introduction
In computing, input/output, or I/O, refers to the communication between an information processing system (such as a computer), and the outside world – possibly a human, or another information processing system. Inputs are the signals or data received by the system, and outputs are the signals or data sent from it. The term can also be used as part of an action; to "perform I/O" is to perform an input or output operation. I/O devices are used by a person (or other system) to communicate with a computer. For instance, keyboards and mouses are considered input devices of a computer, while monitors and printers are considered output devices of a computer. Devices for communication between computers, such as modems and network cards, typically serve for both input and output.
Note that the designation of a device as either input or output depends on the perspective. Mouses and keyboards take as input physical movement that the human user outputs and convert it into signals that a computer can understand. The output from these devices is input for the computer. Similarly, printers and monitors take as input signals that a computer outputs. They then convert these signals into representations that human users can see or read. (For a human user the process of reading or seeing these representations is receiving input.)
In computer architecture, the combination of the CPU and main memory (i.e. memory that the CPU can read and write to directly, with individual instructions) is considered the brain of a computer, and from that point of view any transfer of information from or to that combination, for example to or from a disk drive, is considered I/O. The CPU and its supporting circuitry provide memory-mapped I/O that is used in low-level computer programming in the implementation of device drivers.
Motherboard
The motherboard is a printed circuit which allows communications and transfer data between the various hardware computer parts. Also known as mainboard, mobo, or logic board, planar board…the motherboard contains different connectors for one or more different components such as CPU, Memory, Graphics card and Sound card, Hard disk controller, Floppy disk, CD-in…The motherboard contains as well different connectors for external peripheral devices such as Monitor, Printer, Keyboard, Speaker..., and naturally a special connector for the Power supply.
Cpu
CPU or Central Processing Unit is the brain of your computer. A Central Processing Unit (CPU), or sometimes just called processor, is a description of a class of logic machines that can execute computer programs. This broad definition can easily be applied to many early computers that existed long before the term "CPU" ever came into widespread usage. The term itself and its initialism have been in use in the computer industry at least since the early 1960s . The form, design and implementation of CPUs have changed dramatically since the earliest examples, but their fundamental operation has remained much the same.
Also known as microprocessor or processor, the computer CPU performs the system’s calculating, extracts, decodes and executes instructions.
It establishes good communications between the different components and commands them to execute the tasks. The computer CPU part could be seen as an engineer on the building site.
Memory { ram }
Different computer memory are designed to store data to be executed by the computer.There are the read-only memory or ROM and the random-access memory commonly known as RAM. If the ROM holds instructions for starting up the computer, the RAM is used in other context. Let’s see the next!
The RAM or main memory permits you to read and write data but temporarily. That means as soon as you turned off your computer, you loose whatever data stored in RAM. So why do you need a memory for?
Even if the RAM is a volatile storage area, it is where the CPU has direct access to the program to be executed. You understand that this component is not only important but necessary.
