1st Class

        Introduction         Computer is an electronic device. It requires electricity to work. Computer should be connected to a power socket for supply of power.  

      Other Devices                 UPS     UPS is an uninterrupted power supply, also called uninterruptible power source. It is an electrical apparatus us which provides emergency power to a load when the input power source, typically the utility mains, fails. UPS keeps the computer ON for sometime even after the electricity goes OFF.                     Computer Cables     Computer cables are used for supplying power and commands to computers.        

• A laptop is a personal computer which is designed for mobile use and small and lights enough to sit on a person's lap while in use.                 more...

          Data Storage Devices   After creating any document/image, you need to store them in the computer. Computer stores the information in storage devices i.e. hard disk.                              Floppy Disk Drive      Floppy disk is a common permanent storage media that is used for storing and transporting data from one A floppy disk is composed of a disk of thin, flexible magnetic storage medium encased in a square or rectangular plastic shell. Floppy disks are read and written by a floppy disk drive or FDD. Floppy disks are available in different sizes, these are available in 8-inch (203 mm),  inch (133 mm), and   inch (89 mm) formats.       more...

      Introducing the Output Devices   Did you know! A computer only understands electronic pulses. Computer converts instructions into electronic pulses and processes it using the CPU. After processing the data, it converts the electronic pulses to user understandable form using the output devices. Output devices give the information in the form of picture, sound and text.              The following are the common output devices:

• Monitor
• Printer
• Speaker  

       Monitor Monitor is also called the Visual Display Unit of the computer.                 Monitors are classified into the following types:    

• Colour monitor: It displays the colour images on the more...

          Input Devices    Devices which are used for entering data into a computer are called input devices. Some devices are used for both inputs as well as outputs are called input output devices.          The following are the common input devices:

• Mouse
• Keyboard
• Joystick
• Light pen
• Barcode reader
• Web camera
• Microphone
• Touch Screen  

                    Mouse Mouse is a pointing device that is used to control the movement of the cursor or pointer on a display screen. When mouse is rolled on a flat surface, the mouse pointer on the screen also moves in the corresponding direction. The movement of the mouse ball is translated into signals that tell the computer how and where to move the screen pointer. more...

       Processing Devices   Central Processing Unit (CPU) is the main unit of computer for the data processing. It is also known as the brain of the computer system that carries out the processing of data given and provides the output.         An on/off switch on the front of the cabinet is used for switch on and off the computer system.  CPU assembly contains a CD Rom Drive to insert a CD into it. It has USB ports to connect devices such as Pen Drive, Mouse, mobile, etc                                                                                 

       Keyboard     We use hands to eat, write letters and do many activities. In the same way, computer also needs a device to get information from us. The device through which a computer gets information is called keyboard. (See Figure 1.2.3)    

• The keyboard looks like a typewriter.
• It has many buttons called keys.
• By pressing the keys you can type any letter or number on the screen of your computer. (See Figure 1.2.4)  

             Mouse         Have you ever seen a mouse? The computer mouse is also a small device like a real mouse. (See Figure 1.2.5) The mouse of a computer has a power and data chord similar to more...

      Monitor   Kids!! Do you watch cartoon on the TV? (See Figure 1.2.6)     What does TV do? It shows you the images one by one...    The monitor of the computer looks like a TV screen. (See Figure 1.2.7) It shows words, numbers, pictures and movies on the screen. It displays all the work that you do on the computer.  

       CPU       We use our brain to think and act. Computer also needs a brain to act.... (See Figure 1.2.8) The brain of the computer is called CPU. The CPU looks like a box. CPU stands for Central Processing Unit. The CPU has an ON/OFF switch and some other buttons on it. Some other parts of the computer are the speakers, printer, scanner, UPS and the joystick.    

• Every interfacing device is connected with the central processing unit.
• Everything on the screen of computer is controlled by the input devices.
• Computer displays the information on the screen after calculating the input signals whatever we give in the form of instructions.  

   

• Pointer: A more...

           Introduction   Look at the picture. This is a picture of a boy. His whole body is made up of various parts such as head, neck, legs hands, etc.         In the same way a computer is also made up of different parts. The main parts of the computer are the keyboard, Mouse, Monitor and the CPU.