Input and Output Devices

With respect to class 3 Input and Output Devices, all computers have four basic building blocks for processing.

They are –

• Input devices
• Output devices
• Storage devices
• Central Processing Unit (CPU)

Difference between Input and Output Devices –

Input devices –

• With respect to class 3 computer lessons, an input device is used to feed data to the computer system.
• The data is then used for processing.
• These data are then sent to the Central Processing Unit for processing.

Few input devices –

Keyboard

• With respect to class 3 Input and Output Devices, a keyboard, which looks like a typewriter, is the most common input device of a Computer System.
• Keyboards have the combination of letters and numeric keys.
• We can also keys for volume control, Play / Pause videos etc.
• These keyboards help to capture the data and send it to CPU.

Mouse

• With respect to class 3 Input and Output Devices, to scroll through the monitor screen, a mouse is another commonly used input device.
• It is the cursor on the screen.
• It has two buttons, the left and right clicking buttons and a wheel in the centre for scrolling.
• There are two types of Mouse, one type has a rubber-covered ball at the bottom or using optical sensor.0
• As the mouse is slid on a surface, the ball rolls, resulting in movement of the cursor on the screen.

Scanner

• With respect to class 3 computer lessons, the third important input device of a computer system is a scanner.
• With the help of a scanner, the printed documents are converted to images.
• We have black & white and also colour scanners.
• It works the same way as a Photocopier.

Digital Camera

• Digital Cameras are used to capture images.
• We can transfer these images to our computer.

Output devices –

• The processed information has to be displayed.
• To display this information, there need to be some ‘output devices’. A very useful output device is a VDU (or Visual Display Unit) or a printer.

With respect to class 3 computer lessons, few output devices –

Monitor

• Every computer will have a monitor.
• It is the display screen of a computer.
• Cathode Rays Tube (CRT) and Liquid Crystal Display (LCD) are the two types of Monitors.
• LCD is getting popular because of its slim size and flat screen.

Printers

• With respect to class 3 Input and Output Devices, printers help to get the text/images on a paper.
• We have varieties of printers for various purposes.
• Out textbooks are printed using printers.
• We have black & white printers and also colour printers.

Speakers

• To hear the audio/video file from a computer we need speakers.
• Few systems have built-in speakers and are small in size.
• Big speakers, woofers & sub-woofers are used to enhance sound quality or creating a mini home theatre.

 Recap

Input and Output Devices

Computer's four basic building blocks for processing

With respect to class 3 Input and Output Devices, the difference between Input and Output Devices

• Input devices – An input device is used to feed data to the computer system.

1. Keyboard
2. Mouse
3. Scanner
4. Digital camera

• Output devices – The processed information has to be displayed.

1. Monitor
2. Printer
3. Speaker