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Connecting to the Internet- PC Basics



PC basics

1.1.2 Computers are important building blocks in a network. Therefore, students must be able to identify the major components of a PC. Many networking devices are special purpose computers, with many of the same components as general purpose PCs.


A computer must work properly before it can be used to access information such as Web-based content. This will require students to troubleshoot basic hardware and software problems. Therefore, students must be familiar with the following small, discreet PC components:


Students should also be familiar with the following PC subsystems:

• Transistor – Device that amplifies a signal or opens and closes a circuit.

• Integrated circuit – Device made of semiconductor material that contains many transistors and performs a specific task.

• Resistor – An electrical component that limits or regulates the flow of electrical current in an electronic circuit.

• Capacitor – Electronic component that stores energy in the form of an electrostatic field that consists of two conducting metal plates separated by an insulating material.

• Connector – The part of a cable that plugs into a port or interface.

• Light emitting diode (LED) – Semiconductor device that emits light when a current passes through it.

• Printed circuit board (PCB) – A circuit board which has conducting tracks superimposed, or printed, on one or both sides. It may also contain internal signal layers and power and ground planes. Microprocessors, chips and integrated circuits and other electronic components are mounted on the PCB.

• CD-ROM drive – A device that can read information from a CD-ROM.

• Central processing unit (CPU) – The part of a computer that controls the operation of all the other parts. It gets instructions from memory and decodes them. It performs math and logic operations, and translates and executes instructions.

• Floppy disk drive – A computer drive that reads and writes data to a 3.5-inch, circular piece of metal-coated plastic disk. A standard floppy disk can store approximately 1 MB of information.

• Hard disk drive – A computer storage device that uses a set of rotating, magnetically coated disks called platters to store data or programs. Hard drives come in different storage capacity sizes.

• Microprocessor – A microprocessor is a processor which consists of a purpose-designed silicon chip and is physically very small. The microprocessor utilizes Very Large-Scale Integration (VLSI) circuit technology to integrate computer memory, logic, and control on a single chip. A microprocessor contains a CPU.

• Motherboard – The main printed circuit board in a computer. The motherboard contains the bus, the microprocessor, and integrated circuits used for controlling any built-in peripherals such as the keyboard, text and graphics display, serial ports and parallel ports, joystick, and mouse interfaces.

• Bus – A collection of wires on the motherboard through which data and timing signals are transmitted from one part of a computer to another.

• Random-access memory (RAM) – Also known as read-write memory because new data can be written to it and stored data can be read from it. RAM requires electrical power to maintain data storage. If a computer is turned off or loses power all data stored in RAM is lost.

• Read-only memory (ROM) – Computer memory on which data has been prerecorded. Once data has been written onto a ROM chip, it cannot be removed and can only be read.

• System unit – The main part of a PC, which includes the chassis, microprocessor, main memory, bus, and ports. The system unit does not include the keyboard, monitor, or any external devices connected to the computer.

• Expansion slot – A socket on the motherboard where a circuit board can be inserted to add new capabilities to the computer. Figure shows Peripheral Component Interconnect (PCI) and Accelerated Graphics Port (AGP) expansion slots. PCI is a fast connection for boards such as NICs, internal modems, and video cards. The AGP port provides a high bandwidth connection between the graphics device and the system memory. AGP provides a fast connection for 3-D graphics on computer systems.

• Power supply – The component that supplies power to a computer.

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