Computer Hardware

Computer Hardware are the parts that a computer consists of. The basic computer parts are :
== Motherboard (or Mainboard) ==
The main board that connects all computer parts and manages how data is transferred between them. Motherboards are based on different chips and are suitable for different cpu sockets, that is how the cpu is plugged in the motherboard.
Motherboards come in three different types: ATX, Micro-ATX, and Mini-ITX.  The different types refer to the different sizes.  ATX is the largest, which is housed in the largest tower or case.  Micro-ATX is a bit smaller, and Mini-ITX is the smallest.  Every motherboard has different slots that fit different components.  There can be different video card slots, different numbers of slots, different configurations of video and sound components, different numbers of slots for RAM, and different slots for sound cards and components.  Before you spend potentially hundreds of dollars on components for your motherboard, you must know what type of components will be supported by your motherboard. Also, you have to be sure that the type of CPU you have is supported by your motherboard.  For instance, if you have an Intel i5, 3rd Generation Processor, you must make sure your motherboard supports that technology.  If not, you run the risk of damaging your motherboard, or even worse, your CPU. 
== Central Processing Unit (CPU) ==
This is the "brain" of a computer in which almost all calculations are done. CPUs are usually made of Silicon (though recently, Intel has begun to use Hafnium) and consist of millions of transistors. Usually, the faster the CPU the larger number of transistors it has. The CPU is typically very multipurpose and have a variety of instruction sets to run various types of tasks.
When choosing a CPU for your computer, you must first analyze what the computer will mainly be used for.  Technology for processors changes constantly, so it is also important to keep up on all emerging trends.  For example, if the main user(s) of the computer do not run very many programs simultaneously, it would be wiser to choose a CPU with dual-core technology rather than quad-core.  Dual-core technology acomplishes alot less than a quad-core processor, and is much less expensive.  However, the dual-core processor is still a high funcioning CPU and can accomplish many tasks at a high rate of speed.  If the main user(s) of the computer play a lot of video games, watch a lot of HD movies, and like to multitask would enjoy the benefits of a more expensive, higher functioning quad-core CPU.  This kind of technology, used in conjunction with good graphics and sound cards, would be ideal for such a user.
== Graphics Card (or graphics processing unit) ==
Video cards are responsible for rendering images on the computer monitor. A video card also acts like a dedicated graphics processor which calculates the complicated graphics calculations demanded by computer games and graphics software. Not all computers have discrete video cards. Some computers have onboard video integrated on the motherboard, but these systems are not meant for serious gaming or running heavy graphics applications. 
Recently, GPUs have been made as GPGPUs (general purpose graphics processing units) through native construction (like AMD's FireStream) or patched to do so (NVIDIA's CUDA). Since GPUs are typically far more powerful then a CPU, a GPGPU is capable of a much higher level of performance in such applications.
== Sound Card ==
Sound cards process the sound output that is supposed to come out of computer speakers. Many computers, however do not have discrete sound cards; they have onboard sound integrated on the motherboard. Some audiophiles prefer discrete sound cards because they produce higher quality 
sound with less distortion.
== HDD (Hard Disk Drive) ==
This is where data is stored even after the computer is powered off. Hard disks, however are very slow compared to RAM, but they provide large capacities that can store enormous amounts of data.
== PSU (Power Supply) ==
A power supply unit supplies a computer with electric current converting the high voltage home electricity to a lower voltage electricity that can be used by computer parts.
== Case ==
A computer case is the enclosure inside of which all previous parts are enclosed. Computer cases are usually made of steel or aluminium and have different form factors like ATX, BTX, and mATX.
== Monitor ==
This is the screen that displays all output images and text from the computer. It is made of thousands apon thousands of pixel, this is usually reffered to as resolution.
== Keyboard ==
One of the cheapest computer parts yet one of the most parts dealt with. Keyboards are input devices used to type text into the computer.
== Mouse ==
Like the keyboard, computer mice are very cheap yet computer users are always in contact with them. Mice are input devices that have a little pointer used to point to images and links on the computer screen and click them by means of the mouse buttons. There are usually two basic buttons on a mouse; a right one and a left one. There is also a middle wheel (which functions as a third button as well) used to scroll pages up and down. Some mice have a side wheel or a tilting wheel that can scroll pages right and left.
== External Links ==
Custom PC Guide A regularly updated PC/HTPC buyer's guide.