INFORMATION AND COMMUNICATION TECHNOLOGY (ICT) UGC NET Paper 1 ~ Part 2

Basics of  Computers

WHAT IS A COMPUTER?

• A computer is an electronic and programmable machine, constituting a major part of ICT.
• Computer is a Latin word which means Compute.
• It’s a calculation machine which responds to particular sets of instructions in a well-defined manner.
• It is an electronic device which keeps records of plenty of documents.

 

FOUR FUNCTIONS OF COMPUTER:

 

These are the four most important functions of computer-

• Firstly, Input is the raw information which enters the computer from the input devices.
• Secondly, Process is the operation of data as per given instruction.
• Thirdly, after data processing Output is the processed data which is given by computer.
• Lastly, Storage is the area where data can be kept on permanent basis.

 

SIX ELEMENTS OF COMPUTER:

These are the 6 important elements of Computer-

People: they are the one who operate the computer system.

Procedure: these are written in the hardware and software manuals.

Software: these are the parts that do not have physical existence. They process data into useful information for its users.

Hardware: these are the parts that have physical existence which you can feel and touch.

DATA: It includes all the texts, numbers, sounds, images and videos that one puts into the computer for processing.

Connectivity: internet connectivity is very important to share and access data from all over the world.

 

POTENTIALS OF COMPUTER:

  

 

HARDWARE AND SOFTWARE:

HARDWARE:

These are the parts that have physical existence which you can feel and touch.

For example: such as MOUSE, CPU, Keyboard and scanner.

Hardware consist of INPUT DEVICE and OUTPUT DEVICE.

 

INPUT DEVICES:

Those device through which we can enter data instruction into the computer.

Or we can say it’s an electronic device that is used to enter data and instructions into a computer.

TYPES OF INPUT DEVICE:

KEYBOARD: it’s a device which is recognized as a layout of keys. It has number of keys such as typewriter keyboard (A to Z) with numeric keypad (0- 9), functional keys (FI-F12) and special keys.

POINTING DEVICES: the devices which are used to control a pointer. Such as

• MOUSE
• TRACKBALL
• POINTING STICK
• JOY STICK
• TOUCH PAD
• TOUCH SCREEN
• LIGHT PEN etc.

MOUSE: it is the pointing device i.e. used to control the position of cursor on the screen. There are two types of mouse i.e. Mechanical Mouse, Cordless or wireless Mouse and Optical Mouse.

OPTICAL INPUT DEVICES: it uses light as a source of input. No need for manual entry of data in it. Such as Scanner, Flatbed, Portable Bar Code Reader.

SCANNERS: they are used to copy the images or texts from paper into a digital form that can be used by the computer

BAR CODE READERS (BCR): it is a device which is used for reading printed barcodes with a light beam across the Bar Code.

AUDIO INPUTS: it records the analog sound and convert it into digital form for further processing. For example: Voice Recognition, Microphone, Musical Instrument Digital.

VIDEO INPUTS: these are the devices which can be used to enter full motion recording into the computer. For example: Digital Camera, Video Capture Card.

Others Input Devices are Biometric device, Web Cam, OMR (Optical Mark Reader), OCR (Optical Character Reader), MICR (Magnetic Link Character Reader), Card Readers, Graphic Tablets & Styles, Smart Pen and Microphones.

OUTPUT DEVICES:

These are the devices through which users can get output or information from the computer such as CRT Monitor, TFT Monitor, Laser Printer, Inkjet Printer, Dot Matrix Printer, Speaker, Plotters, Multimedia Projectors.

TYPES OF OUTPUT DEVICES:

MONITOR (VISUAL DISPLAY UNIT): it is a device which shows computer output on a screen. The output on screen is called as SOFT COPY.

 FEATURES OF MONITOR:

RESOLUTION: the number of pixels per inch is known as resolution (1 mega pixel = 1 million pixel). Pixel is the smallest unit of monitor. Every pixel has 3 color dots i.e., RGB (RED, GREEN, BLUE). The resolution can be measured in terms of DPI (Dots per Inch) and PPI (Pixel Per Inch).

TYPES OF MONITORS:

Cathode Ray Tube (CRT)

Liquid Crystal Display (LCD)

Liquid Emissions Diode (LED)

 

PRINTER: it’s a device that produces the hard copy or physical copy of the output.

 

TYPES OF PRINTERS:

IMPACT PRINTERS: these are the first-generation printers. There is mechanical contact between paper and printing head in impact printers. For example, typewriters, Dot Matrix Printer, Daisy Wheel Printer. These printers are cheap but time consuming and their quality is poor.

NON-IMPACT PRINTERS: there is no mechanical relationship between paper and printing head. For example: Laser Printer, Ink-Jet Printer and Thermal Printer.

Printers work on the principle of WYSIWYG i.e., WHAT YOU SEE IS WHAT YOU GET.

PROJECTORS: these devices are used to display computer information on big screen.

 

PLOTTER: It is a device which is used to produce high quality graphics in different colors. They are also used to draw architecture, coding, maps etc.

TYPES OF PLOTTERS:

FLATBED PLOTTERS

DRUM PLOTTER.

 

AUDIO OUTPUT DEVICE: these are used to translate audio information from computers into sound in such a way that can be understood by all. There are Speakers and Headphones which are used for it.

Other output devices are Fax Machines, Multifunction Devices, Internet Telephones and Terminals