How Computers Work

• Central Processing Unit (CPU) or Processor

The Central Processing Unit (CPU) or Processor is located inside of the computer case on the motherboard. Its job is to carry out commands and it is sometimes referred to as the brain of the computer. When you press a key, click the mouse or run a program, the command is sent to the CPU. Two well known companies who make this for PC’s are Intel and AMD.
Source: http://www.gcflearnfree.org/computerbasics/7

• Motherboard or Mainboard

The motherboard is the computer’s main circuit board. It is a thin plate that holds the CPU memory, connectors for the hard drive, expansion cards that control the audio and video and connections to your computer's ports, like the USB port. The motherboard connects to every part of the computer in some way. Two well known companies that manufacture this part for PC’s are Acer and ACube Systems.
Source: http://www.gcflearnfree.org/computerbasics/7 and https://en.wikipedia.org/wiki/List_of_computer_hardware_manufacturers

• Power Supply Unit

The Power Supply Unit in a computer converts the power from the wall outlet into the type of power needed by the computer. It sends power to the motherboard where it can be sent to the other components, either through the motherboard or from the Power Supply Unit. Two companies that make this component for PC’s are Antec and BFG Technologies.
Source: http://www.gcflearnfree.org/computerbasics/7 and https://en.wikipedia.org/wiki/Category:Computer_power_supply_unit_manufacturers

• Random Access Memory (RAM)

RAM if the short-term-memory of a computer’s system. Whenever your computer performs calculations, the data is temporarily stored in the RAM until it is needed. This memory is automatically erased when the computer is turned off. If you’re working on a document, spreadsheet or other type of file, you need to manually save it or it will be lost when your system loses power or is shut off. When you save these files they are moved to the Hard Drive, which acts as a long-term memory for the computer. The more RAM you have, the more things your computer can do at the same time. If you don't have enough RAM, you may notice that your computer is sluggish when you have several programs open. Because of this, many people add extra RAM to their computers. Two manufacturers that create RAM components for computers are ADATA and Lenovo.
Source: http://www.gcflearnfree.org/computerbasics/7.2 and https://en.wikipedia.org/wiki/List_of_computer_hardware_manufacturers

• Hard Drive

The hard drive on your computer is where the software is installed and it is also where your documents and other saved files are stored. The Hard Drive is your system's long-term storage, so whatever is saved to the hard drive is kept even after turning the system off or unplugging it. The faster the Hard Drive is, the faster your computer can start up and load programs. Two manufacturers that create Hard Drives for PC’s are Western Digital and Seagate Technology.
Source: http://www.gcflearnfree.org/computerbasics/7.2 and http://www.southjerseydata.com/hard-drive-manufacturers.html

• Video Card

A video card is responsible for what you see on your computer’s monitor. Most computers have a GPU (graphics processing unit) built into the motherboard instead of having a separate video card. Some people will add video cards to their computer’s system if they play graphic-intensive games so a more clear image will appear and generally will be more appealing to the user. Two manufacturers that create video cards are Asus and MSI.
Source: http://www.gcflearnfree.org/computerbasics/7.3 and http://www.ranker.com/list/the-best-video-card-manufacturers/computer-hardware?var=2&utm_expid=16418821-179.vk2gM_coRrOMcxn9T2riGQ.1&utm_referrer=https%3A%2F%2Fwww.google.ca%2F

• Sound Card

The sound card, also called an audio card, is responsible for what you hear in the speakers or headphones. Most motherboards have integrated sound, but you can upgrade your system’s sound with a sound card. Two manufacturers that create sound cards are Asus and Diamond Multimedia.
Source: http://www.gcflearnfree.org/computerbasics/7.3 and https://en.wikipedia.org/wiki/List_of_computer_hardware_manufacturers#Sound_cards

• Network Card

A network card allows your computer to communicate over a network and access the Internet. It can either connect with an Ethernet cable or through a wireless connection (often called Wi-Fi). Most motherboards have some sort of built in network connections, and a network card can be added to an expansion slot. Two leading manufacturers that create network cards are Asus and Intel.
Source: http://www.gcflearnfree.org/computerbasics/7.3 and https://en.wikipedia.org/wiki/List_of_computer_hardware_manufacturers#Network_cards_.28NIC.29