Data Communications

           Data Communication is the process of moving information from one point to another by means of some transmission system. Network           A network is a collection of entities that exchange information or good. Few examples of networks are railway system, nervous system of animals, telephone system. Communications Network           A communications network is a system of interconnected computers, and communication devices that can communicate with one another and share resources. At the most elementary level, a computer network consists  of two computers connected with...

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Application Software

               Application software is designed to perform useful general-purpose tasks. For example, an application program called Solitaire is a single program that lets you play a card game. Application software can be grouped as customized software or as application packages. Customized software is generally designed for a particular customer whereas application packages are "off the shelf" programmes designed for the general public. Common types of application software are: Word Processing Spreadsheet Database Management System Presentation Software Desktop Publishing and Graphic Design Web Design and Development Device Drivers               ...

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System Software

Software           Software refers to instructions which are used by  the computer to perform various tasks. The word programme is synonymous with software. Software is created with programming languages and related utilities. Software is generally classified into two types: System Software and Application Software. System Software           System software is responsible for controlling, integrating and managing the individual hardware components of a computer system so that other software and the users of the system see it as a functional unit without having to be concerned with the low-level details of the computer hardware. System software can be further classified as: Operating Systems. Utilities...

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Different Types of Printers

            Many different types of printers are in use today. Two primary technologies used for printing are impact printing and non-impact printing. Impact Printers use a print head containing a number of metal pins which strike an inked ribbon placed between the print head and the paper. The non-impact printers are much quieter than impact printers as their printing heads do not strike the paper. The Most Common Printer Types Are: Dot matrix printers, Ink-jet printers, Laser printers.  Dot Matrix Printers               These printers work by firing a matrix of tiny pins (which are located in the...

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Different Types of Display Screens

CRT Monitor                   A cathode-ray tube and associated electronics connected to the video output of a computer. These have higher resolution than TVs. Lager monitors with high resolution are used for specialized application such as desktop publishing and CAD. LCD (Liquid Crystal Display) Monitor                LCDs are screens made from two glass/plastic plates with liquid in between. LCDs are commonly used for calculators and laptop computers, as they are far flatter than is possible with cathode ray screens used in TVs and Standard computer monitors. Main difference...

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Different Types of Output Devices

             Output devices translate information processed by the computer into a form that either humans or other machines can understand. There are a variety of output devices, which can be connected to a computer. Some of the common output devices are explained in the following sections. Monitor             The most common form of output is the computer screen. It is more correctly called 'monitor' and sometimes referred to as the visual display or VDU.              The quality of a computer monitor is based on the following properties: Resolution: Resolution is the number of pixels, which the screen can display. A 'pixel' is the...

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Different Types of Input Devices

Formatting             Hard disks and Diskettes must be formatted before saving data on them. Formatting can be considered as an initialization process that prepares the disk or diskette electronically so that it can store data or programs. Input Devices             Input devices enable data to be fed into the computer in a form that the computer can use. Input devices are categorized into two types: keyboard entry devices and direct entry devices. A devices through which data can be entered to the computer by pressing keys is called a keyboard entry device whereas all the other types of input devices are called direct entry...

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Different Types of Memory

Floppy Disk            A floppy disk or a diskette is a round flat removable piece of plastic coated with a Ferric Oxide layer, and encased in a protective plastic cover, called the disk jacket. The Ferric Oxide layer is capable of holding a magnetic field. Data is stored on a floppy disk by means of a disk drive, which alters the magnetic orientation of the particles in the Ferric Oxide layer. Reading data from a diskette means that the data stored as a magnetic pattern on a diskette is converted to electronic signals and transmitted to the memory of the computer. Writing data on a diskette means electronic information is transformed into magnetic patterns and recorded magnetically on...

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