Archive for the 'CCNA' Category

PC basics

October 18, 2006

Because computers are important building blocks in a network, it is important to be able to recognize and name the major components of a PC.

Small, Discrete Components

  • Transistor – Device that amplifies a signal or opens and closes a circuit.
  • Integrated circuit (IC) – Device made of semiconductor material that contains many transistors and performs a specific task.
  • Resistor – Device made of material that opposes the flow of electric current.
  • 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.

Personal Computer Subsystems

  • Printed circuit board (PCB) – A thin plate on which chips or integrated circuits and other electronic components are placed.
  • CD-ROM drive – Compact disk read-only memory drive, which is a device that can read information from a CD-ROM.
  • Central processing unit (CPU) – The brains of the computer where most calculations take place. 
  • Floppy disk drive – A disk drive that can read and write to floppy disks. 
  • Hard disk drive – The device that reads and writes data on a hard disk.
  • Microprocessor – A silicon chip that contains a CPU.
  • Motherboard – The main circuit board of a microcomputer 
  • Bus – A collection of wires through which data is transmitted from one part of a computer to another.
  • Random-access memory (RAM) – Also known as Read-Write memory, new data can be written to it and stored data can be read from it. RAM requires electrical power to maintain data storage. If the 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. 
  • Power supply – The component that supplies power to a computer.

Backplane Components

  • Backplane – The large circuit board that contains sockets for expansion cards.
  • Network interface card (NIC) – An expansion board inserted into a computer so that the computer can be connected to a network.
  • Video card – A board that plugs into a PC to give it display capabilities.
  • Audio card – An expansion board that enables a computer to manipulate and output sounds.
  • Parallel port – An interface capable of transferring more than one bit simultaneously that is used to connect external devices such as printers.
  • Serial port – An interface that can be used for serial communication, in which only 1 bit is transmitted at a time.
  • Mouse port – A port designed for connecting a mouse to a PC.
  • Power cord – A cord used to connect an electrical device to an electrical outlet that provides power to the device.

Think of the internal components of a PC as a network of devices, which are all attached to the system bus. In a sense, a PC is a small computer network.

MORE INFO : http://www.jegsworks.com/Lessons/ lessonintro.htm