Nowadays, we live in a world of technology in which the use of computers is essential. Computers can be used for so many activities and purposes that we cannot even imagine not being able to have access to a computer which we might work with. We use computers not only at work and at school but also at home for all sorts of activities which we enjoy doing in our spare time. Computers have been very much improved in the last few years because there have been many changes made to their components. These changes widely influenced the performance of modern computers which users have appreciated more especially because of these improved features included within them. Users are very much interested in always being aware of the latest technology and the changes it brings so that they might also be able to improve their computers and the ways in which they work with them, as well as the results being achieved by using them. In this respect, many users have become more interested in finding out besides the basic notions related to their computers also some details related to what types of computer hardware they can find within their PCs, what functions these components have within their computer system and how they could be improved.

When discussing about what types of computer hardware can be found within a PC it is important to be mentioned the fact that hardware refers to components which can be seen and touched within computers and in this way users should not have any problem with finding and analyzing them. It is also important for users to be aware of the fact that these hardware components are known to be categorized as it follows: input types of components, output components, storage devices, processing components and communicating devices.

These five categories should enable users to understand what types of computer hardware can be found and what are the main functions of these components within a computer before learning more detailed information about each of these components. In this respect, as the names of these categories suggest we can find within a computer components which have input functions, which means that they are used to type certain instructions and information which act as input for the computer system which will have to operate them. Output components are certainly the ones on which the results of this operation of the instructions will be displayed. Storage devices could not deal with anything else than the storage of the necessary data and instructions within the computer system. Processing components are the ones dealing with the processing of the information given by input components in order to display the necessary results on the output type of devices. All of these components are very important within the computer system because they all have their specific roles in determining the performance of the computer system. It is also important for users to become aware of the fact that some of these components are actually essential for the computer system to be able to operate.


When discussing about what types of computer hardware users can identify within their PCs it is important to mention some examples. In this respect, it can be sad that among the hardware components very important are: the monitor, the motherboard, the computer case, the central processing unit, the random access memory, the hard drive, the power supply, the keyboard, the mouse, the printer, the modem, the cables, the chipset, the buses and others. As it can be seen, there are numerous types of hardware components included within a computer. Users should also become familiar with the fact that there are various models of the same hardware components available on the market. In this respect, users should also know that there are certain common hardware components which ca be fund in any computer and that there re also certain specific components which can differ form one computer to another. This type of data might be useful for users in their understanding of the way in which their computer functions in comparison with other computers.




All of these hardware components are very important to be analyzed when discussing about what types of computer hardware are found within a PC and what functions they have within the computer system.  For example, the motherboard is known to be very important because it includes many of the hardware components which are essential for the computer system to be able to operate. The central processing unit, one of the components found on the computer motherboard is essential for any computer because it is considered its brain. This is because the central processing unit deals with the main functions of the computer system and with the instructions which need to be operated by this system in order to offer users the opportunity to have the necessary results displayed on their computer screens. The random access memory, which is a storage computer device, is very important because it allows users to access all sorts of data being stored within the computer in a random order that they might choose. It is also important because it represents the main memory within the computer system. Another very important hardware component is the power supply, which gives the necessary power to other hardware components in order for them to function and in this way to enable the computer system to operate.




In any discussion on what types of computer hardware can be found it is important to be mentioned the importance of these components and the fact that good hardware components determine for the computer which includes them to also be a very good quality one. Users have to pay attention to what types of computer hardware they have when they need to work with their computers very much and to obtain good results by working with them. They need to have good input components, good output devices, good processing components and storage devices in order to work easier, better and faster with their computers.

The hardware are the parts of computer itself including the Central Processing Unit (CPU) and related microchips and micro-circuitry, keyboards, monitors, case and drives (hard, CD, DVD, floppy, optical, tape, etc...). Other extra parts called peripheral components or devices include mouse, printers, modems, scanners, digital cameras and cards (sound, colour, video) etc... Together they are often referred to as a personal computer.
Central Processing Unit - Though the term relates to a specific chip or the processor a CPU's performance is determined by the rest of the computer's circuitry and chips.
Currently the Pentium chip or processor, made by Intel, is the most common CPU though there are many other companies that produce processors for personal computers. Examples are the CPU made by Motorola and AMD.

Though there were many computers using many different processors previous to this I call the 80286 processor the advent of home computers as these were the processors that made computers available for the average person. Using a processor before the 286 involved learning a proprietary system and software. Most new software are being developed for the newest and fastest processors so it can be difficult to use an older computer system.
Keyboard - The keyboard is used to type information into the computer or input information. There are many different keyboard layouts and sizes with the most common for Latin based languages being the QWERTY layout (named for the first 6 keys). The standard keyboard has 101 keys. Notebooks have embedded keys accessible by special keys or by pressing key combinations (CTRL or Command and P for example). Ergonomically designed keyboards are designed to make typing easier. Hand held devices have various and different keyboard configurations and touch screens.
Some of the keys have a special use. There are referred to as command keys. The 3 most common are the Control or CTRL, Alternate or Alt and the Shift keys though there can be more (the Windows key for example or the Command key). Each key on a standard keyboard has one or two characters. Press the key to get the lower character and hold Shift to get the upper.
Removable Storage and/or Disk Drives - All disks need a drive to get information off - or read - and put information on the disk - or write. Each drive is designed for a specific type of disk whether it is a CD, DVD, hard disk or floppy. Often the term 'disk' and 'drive' are used to describe the same thing but it helps to understand that the disk is the storage device which contains computer files - or software - and the drive is the mechanism that runs the disk.
Digital flash drives work slightly differently as they use memory cards to store information so there are no moving parts. Digital cameras also use Flash memory cards to store information, in this case photographs. Hand held devices use digital drives and many also use memory cards.
Mouse - Most modern computers today are run using a mouse controlled pointer. Generally if the mouse has two buttons the left one is used to select objects and text and the right one is used to access menus. If the mouse has one button (Mac for instance) it controls all the activity and a mouse with a third button can be used by specific software programs.
One type of mouse has a round ball under the bottom of the mouse that rolls and turns two wheels which control the direction of the pointer on the screen. Another type of mouse uses an optical system to track the movement of the mouse. Laptop computers use touch pads, buttons and other devices to control the pointer. Hand helds use a combination of devices to control the pointer, including touch screens.

Note: It is important to clean the mouse periodically, particularly if it becomes sluggish. A ball type mouse has a small circular panel that can be opened, allowing you to remove the ball. Lint can be removed carefully with a tooth pick or tweezers and the ball can be washed with mild detergent. A build up will accumulate on the small wheels in the mouse. Use a small instrument or finger nail to scrape it off taking care not to scratch the wheels. Track balls can be cleaned much like a mouse and touch-pad can be wiped with a clean, damp cloth. An optical mouse can accumulate material from the surface that it is in contact with which can be removed with a finger nail or small instrument.

Monitors - The monitor shows information on the screen when you type. This is called outputting information. When the computer needs more information it will display a message on the screen, usually through a dialog box. Monitors come in many types and sizes. The resolution of the monitor determines the sharpness of the screen. The resolution can be adjusted to control the screen's display..
Most desktop computers use a monitor with a cathode tube or liquid crystal display. Most notebooks use a liquid crystal display monitor.

To get the full benefit of today's software with full colour graphics and animation, computers need a color monitor with a display or graphics card.
Printers - The printer takes the information on your screen and transfers it to paper or a hard copy. There are many different types of printers with various levels of quality. The three basic types of printer are; dot matrix, inkjet, and laser.

• Dot matrix printers work like a typewriter transferring ink from a ribbon to paper with a series or 'matrix' of tiny pins.
• Ink jet printers work like dot matrix printers but fires a stream of ink from a cartridge directly onto the paper.
• Laser printers use the same technology as a photocopier using heat to transfer toner onto paper.

Modem - A modem is used to translate information transferred through telephone lines, cable or line-of-site wireless.
The term stands for modulate and demodulate which changes the signal from digital, which computers use, to analog, which telephones use and then back again. Digital modems transfer digital information directly without changing to analog.
Modems are measured by the speed that the information is transferred. The measuring tool is called the baud rate. Originally modems worked at speeds below 2400 baud but today analog speeds of 56,000 are standard. Cable, wireless or digital subscriber lines can transfer information much faster with rates of 300,000 baud and up.
Modems also use Error Correction which corrects for transmission errors by constantly checking whether the information was received properly or not and Compression which allows for faster data transfer rates. Information is transferred in packets. Each packet is checked for errors and is re-sent if there is an error.
Anyone who has used the Internet has noticed that at times the information travels at different speeds. Depending on the amount of information that is being transferred, the information will arrive at it's destination at different times. The amount of information that can travel through a line is limited. This limit is called bandwidth.
There are many more variables involved in communication technology using computers, much of which is covered in the section on the Internet.
Scanners- Scanners allow you to transfer pictures and photographs to your computer. A scanner 'scans' the image from the top to the bottom, one line at a time and transfers it to the computer as a series of bits or a bitmap. You can then take that image and use it in a paint program, send it out as a fax or print it. With optional Optical Character Recognition (OCR) software you can convert printed documents such as newspaper articles to text that can be used in your word processor. Most scanners use TWAIN software that makes the scanner accessable by other software applications.
Digital cameras allow you to take digital photographs. The images are stored on a memory chip or disk that can be transferred to your computer. Some cameras can also capture sound and video.
Case - The case houses the microchips and circuitry that run the computer. Desktop models usually sit under the monitor and tower models beside. They come in many sizes, including desktop, mini, midi, and full tower. There is usually room inside to expand or add components at a later time. By removing the cover off the case you may find plate covered, empty slots that allow you to add cards. There are various types of slots including IDE, ASI, USB, PCI and Firewire slots.
Depending on the type notebook computers may have room to expand . Most Notebooks also have connections or ports that allows expansion or connection to exterior, peripheral devices such as monitor, portable hard-drives or other devices.
Cards - Cards are components added to computers to increase their capability. When adding a peripheral device make sure that your computer has a slot of the type needed by the device.

Sound cards allow computers to produce sound like music and voice. The older sound cards were 8 bit then 16 bit then 32 bit. Though the human ear can't distinguish the fine difference between sounds produced by the more powerful sound card they allow for more complex music and music production.
Colour cards allow computers to produce colour (with a colour monitor of course). The first colour cards were 2 bit which produced 4 colours [CGA]. It was amazing what could be done with those 4 colours. Next came 4 bit allowing for 16 [EGA and VGA ] colours. Then came 16 bit allowing for 1064 colours and then 24 bit which allows for almost 17 million colours and now 32 bit and higher allow monitors to display almost a billion separate colours.
Video cards allow computers to display video and animation. Some video cards allow computers to display television as well as capture frames from video. A video card with a digital video camera allows computers users to produce live video. A high speed connection is required for effective video transmission.
Network cards allow computers to connect together to communicate with each other. Network cards have connections for cable, thin wire or wireless networks. For more information see the section on Networks.

Cables connect internal components to the Motherboard, which is a board with series of electronic path ways and connections allowing the CPU to communicate with the other components of the computer.
Memory - Memory can be very confusing but is usually one of the easiest pieces of hardware to add to your computer. It is common to confuse chip memory with disk storage. An example of the difference between memory and storage would be the difference between a table where the actual work is done (memory) and a filing cabinet where the finished product is stored (disk). To add a bit more confusion, the computer's hard disk can be used as temporary memory when the program needs more than the chips can provide.
Random Access Memory or RAM is the memory that the computer uses to temporarily store the information as it is being processed. The more information being processed the more RAM the computer needs.
One of the first home computers used 64 kilobytes of RAM memory (Commodore 64). Today's modern computers need a minimum of 64 Mb (recommended 128 Mb or more) to run Windows or OS 10 with modern software.
RAM memory chips come in many different sizes and speeds and can usually be expanded. Older computers came with 512 Kb of memory which could be expanded to a maximum of 640 Kb. In most modern computers the memory can be expanded by adding or replacing the memory chips depending on the processor you have and the type of memory your computer uses. Memory chips range in size from 1 Mb to 4 Gb. As computer technology changes the type of memory changes as well making old memory chips obsolete. Check your computer manual to find out what kind of memory your computer uses before purchasing new memory chips.

A personal computer is made up of multiple physical components of computer hardware, upon which can be installed an operating system and a multitude of software applications to perform the operator's desired functions.
Though a PC comes in many different forms, a typical personal computer consists of a case or chassis in a tower shape (desktop), containing components such as a motherboard.

Contents [hide] 1 Motherboard 2 Power supply 3 Removable media devices 4 Secondary storage 5 Sound card 6 Input and output peripherals 6.1 Input 6.2 Output 7 See also

[edit] Motherboard

The motherboard is the main component inside the case. It is a large rectangular board with integrated circuitry that connects the rest of the parts of the computer including the CPU, the RAM, the disk drives (CD, DVD, hard disk, or any others) as well as any peripherals connected via the ports or the expansion slots.
Components directly attached to the motherboard include:

• The central processing unit (CPU) performs most of the calculations which enable a computer to function, and is sometimes referred to as the "brain" of the computer. It is usually cooled by a heat sink and fan.
• The chip set mediates communication between the CPU and the other components of the system, including main memory.
• RAM (Random Access Memory) stores all running processes (applications) and the current running OS.
• The BIOS includes boot firmware and power management. The Basic Input Output System tasks are handled by operating system drivers.
• Internal Buses connect the CPU to various internal components and to expansion cards for graphics and sound.
  • Current
    • The north bridge memory controller, for RAM and PCI Express
      • PCI Express, for expansion cards such as graphics and physics processors, and high-end network interfaces
    • PCI, for other expansion cards
    • SATA, for disk drives
  • Obsolete
    • ATA (superseded by SATA)
    • AGP (superseded by PCI Express)
    • VLB VESA Local Bus (superseded by AGP)
    • ISA (expansion card slot format obsolete in PCs, but still used in industrial computers)
• External Bus Controllers support ports for external peripherals. These ports may be controlled directly by the south bridge I/O controller or based on expansion cards attached to the motherboard through the PCI bus.
  • USB
  • FireWire
  • eSATA
  • SCSI

[edit] Power supply

A power supply unit (PSU) converts alternating current (AC) electric power to low-voltage DC power for the internal components of the computer. Some power supplies have a switch to change between 230 V and 115 V. Other models have automatic sensors that switch input voltage automatically, or are able to accept any voltage between those limits. Power supply units used in computers are nearly always switch mode power supplies (SMPS). The SMPS provides regulated direct current power at the several voltages required by the motherboard and accessories such as disk drives and cooling fans.

[edit] Removable media devices

• CD (compact disc) - the most common type of removable media, suitable for music and data.
  • CD-ROM Drive - a device used for reading data from a CD.
  • CD Writer - a device used for both reading and writing data to and from a CD.
• DVD (digital versatile disc) - a popular type of removable media that is the same dimensions as a CD but stores up to 12 times as much information. It is the most common way of transferring digital video, and is popular for data storage.
  • DVD-ROM Drive - a device used for reading data from a DVD.
  • DVD Writer - a device used for both reading and writing data to and from a DVD.
  • DVD-RAM Drive - a device used for rapid writing and reading of data from a special type of DVD.
• Blu-ray Disc - a high-density optical disc format for data and high-definition video. Can store 70 times as much information as a CD.
  • BD-ROM Drive - a device used for reading data from a Blu-ray disc.
  • BD Writer - a device used for both reading and writing data to and from a Blu-ray disc.
• HD DVD - a discontinued competitor to the Blu-ray format.
• Floppy disk - an outdated storage device consisting of a thin disk of a flexible magnetic storage medium. Used today mainly for loading RAID drivers.
• Iomega Zip drive - an outdated medium-capacity removable disk storage system, first introduced by Iomega in 1994.
• USB flash drive - a flash memory data storage device integrated with a USB interface, typically small, lightweight, removable, and rewritable. Capacities vary, from hundreds of megabytes (in the same ballpark as CDs) to tens of gigabytes (surpassing, at great expense, Blu-ray discs).
• Tape drive - a device that reads and writes data on a magnetic tape, used for long term storage and backups.

[edit] Secondary storage

Hardware that keeps data inside the computer for later use and remains persistent even when the computer has no power.

• Hard disk - for medium-term storage of data.
• Solid-state drive - a device similar to hard disk, but containing no moving parts and stores data in a digital format.
• RAID array controller - a device to manage several internal or external hard disks and optionally some peripherals in order to achieve performance or reliability improvement in what is called a RAID array.

[edit] Sound card

Enables the computer to output sound to audio devices, as well as accept input from a microphone. Most modern computers have sound cards built-in to the motherboard, though it is common for a user to install a separate sound card as an upgrade. Most sound cards, either built-in or added, have surround sound capabilities.

[edit] Input and output peripherals

Input and output devices are typically housed externally to the main computer chassis. The following are either standard or very common to many computer systems.

[edit] Input

• Text input devices
  • Keyboard - a device to input text and characters by depressing buttons (referred to as keys).
• Pointing devices
  • Mouse - a pointing device that detects two dimensional motion relative to its supporting surface.
    • Optical Mouse - uses light to determine mouse motion.
  • Trackball - a pointing device consisting of an exposed protruding ball housed in a socket that detects rotation about two axes.
  • Touchscreen - senses the user pressing directly on the display

• Gaming devices
  • Joystick - a control device that consists of a handheld stick that pivots around one end, to detect angles in two or three dimensions.
  • Gamepad - a handheld game controller that relies on the digits (especially thumbs) to provide input.
  • Game controller - a specific type of controller specialized for certain gaming purposes.
• Image, Video input devices
  • Image scanner - a device that provides input by analyzing images, printed text, handwriting, or an object.
  • Webcam - a low resolution video camera used to provide visual input that can be easily transferred over the internet.
• Audio input devices
  • Microphone - an acoustic sensor that provides input by converting sound into electrical signals.

[edit] Output

• Printer - a device that produces a permanent human-readable text of graphic document.
• Speakers - typically a pair of devices (2 channels) which convert electrical signals into audio.
  • Headphones - for a single user hearing the audio.
• Monitor - an electronic visual display with textual and graphical information from the computer.
  • CRT - (Cathode Ray Tube) as of 2010, it is a mostly obsolete technology replaced by LCD panels.
  • LCD - (Liquid Crystal Display) as of 2010, it is the primary visual display for personal computers.

[edit] See also

• Glossary of computers

[hide] v • d • e Basic computer components Input devices Keyboard · Light pen · Mouse · Microphone · Webcam Output devices Monitor  · Speakers  · Printer Removable data storage Floppy disk · Compact Disc ReWritable/DVD Drive · USB flash drive · Memory card Computer case Central processing unit · RAM · Video card · Sound card · Motherboard · Power supply · Hard drive Data ports Serial port · Parallel port · Universal Serial Bus (USB)