principal part of the computer

principal part

PRINCIPAL PARTS OF THE COMPUTUER

Software refers to parts of the computer which do not have a material form, such as programs, data, protocols, etc. When software is stored in hardware that cannot easily be modified

HADWARE:the trem hadware covers all or those parts of a computer that are tangible objects.Circuits, display,power supiess,cables,keyboard ,printer,asnd mice are all hadware.

CONTROL UNIT: the control unit(often calleed a control system or central controller) manages the computer's various components ;it read and interprets(decodes)the program instruccion transforming them into a series of control signal which active other part of the computer.
MEMORY: a computrer's memory can be viewed as a list of cells into which numbers can be placed or read . other parts of the computer: 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 - 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.

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 .

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 >keyboard layout is any specific mechanical, visual, or functional arrangement of the keys, legends, or key–meaning associations (respectively) of a computer, typewriter, or other typographic keyboard.

• Mechanical layout: The placements and keys of a keyboard.



• Visual layout: The arrangement of the legends (markings) that appear on the keys of a keyboard.



• Functional layout: The arrangement of the key–meaning associations, determined in software, of all the keys of a keyboard.