All physical parts of the computer (or everything that we can touch) is known as hardware. All of the components of a computer system can be summarised with the simple equations below...
Software gives "intelligence" to the computer.
Basically all computers, regardless of their size, have the same general design which consist of the following units: the central processing unit (CPU), memory, and input/output circuitry which are situated on the printed circuit board, also called the system board or motherboard (figure of a motherboard).
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| Figure 2. This diagram describes the relationships between the components of the computer system. |
The microprocessor is an integrated circuit that contains transistors, diodes, resistors, and other components interconnected to form the electronic circuit. The circuit is mounted in a metal or plastic package and connections are welded to external pins. The circuit can be accessed only through these pins. This design produces the following benefits:
a reduction in size, cost, and power consumption;
Large computer systems can have many processors, so they are called multiprocessor systems. The microcomputer is a system with a single processor that fits on a single chip. This processor is called a microprocessor.
The RAM and ROM chips provide memory to the computer. One of the most important characteristics of memory is the amount of information it can hold.
The input/output(I/O) devices are external devices (in relation to the CPU) that are connected to the computer to provide means of the communication between the user and the computer.
Disks (floppy, hard, or optical) and tapes are used to store information for long periods of time.
Peripheral devices are connected to the computer through ports, or sockets, that are mounted outside. Some peripherals (e.g. disk drives) are located inside the computer case, so they are connected via expansion slots.
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a). The back of the computer showing the ports and sockets | b). Expansion slots |
Figure 3. How peripheral devices are connected to the computer
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