A computer must work properly before it can be used to access information such as Web-based content. This will require users to troubleshoot basic hardware and software problems. Therefore, users must be familiar with the following small, discreet PC components:
 
Users should also be familiar with the following PC subsystems:
  • TransistorDevice 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.
  • CapacitorElectronic component that stores energy in the form of an electrostatic field that consists of two conducting metal plates separated by an insulating material.
  • ConnectorThe 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 driveA 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.
  • Power supply The component that supplies power to a computer.
The following backplane components are also important:
  • BackplaneA backplane is an electronic circuit board containing circuitry and sockets into which additional electronic devices on other circuit boards or cards can be plugged; in a computer, generally synonymous with or part of the motherboard.
  • 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 portAn interface that can be used for serial communication in which only one bit is transmitted at a time.
  • Mouse port A port used to connect a mouse to a PC.
  • USB port A Universal Serial Bus connector. A USB port connects devices such as a mouse or printer to the computer quickly and easily.
  • Firewire A serial bus interface standard offering high-speed communications and isochronous real-time data services.
  • Power cord A cord used to connect an electrical device to an electrical outlet that provides power to the device.