3. Input Devices

A large number of different devices are to allow users to give information, or input, to the computer. Text, numbers, sound, graphics, video, movement, heat, touch, etc., can all be entered using the correct device.

1. Keyboards

This is the main input device for desktop and laptop systems. It has keys for: • text entry • entering numbers • carrying out special functions such as printing the screen display.

 

2. Mouse and Trackball

A mouse is the other standard input device supplied with desktop computers. It is a pointing device that allows the user to move a pointer or cursor across a monitor screen. The mouse is a very important input device. It helps you to do many things, such as: controlling the cursor or pointer opening up menus selecting items from menus by clicking the mouse button opening up software by clicking the mouse button dragging icons to move them into folders, to save files..

Movie: 5. Keyboard and Mouse

 

Recent changes to improve the functionality of ‘mice’ include cordless mice, optical mice, scroll wheels and extra buttons. Trackball Works like an upside down mouse. Users move the ball which in turn moves a cursor on the screen.

 

3. Track Pads

	Track pads are found on laptops. The track pad does the job of the mouse and lets you: control the cursor by ragging our finger across the pad select items from menus or open up files by tapping on the pad.
Movie: 6. Track Pads.

 

4. Graphics Tablet

This has a flat surface that can sense the slightest touch. Artists and designers use it to enter drawings into a computer system. By dragging a stylus across the tablet surface you can draw freehand and the drawing is entered exactly into the computer’s memory
Movie: 7. Graphics Tablet.

 

5. Microphone

Microphones can be used to capture sound and store them on backing storage. Recently it has become possible to use broadband internet connections to make phone calls with the use of microphones.

 

6. Scanner

Used to capture or input pictures and text into computer systems. They work by shining a light onto a page in the scanner. A detectors picks up the levels of light reflected from the page and these are turned into digital numbers which are then processed by the computer. Special Optical Recognition Programs (OCR) can be used to recognise text. These programs will turn pictures representing text on a page into a document which can be processed by a word processor program.

 

7. Cameras

Cameras are used to capture moving and still images. With photo sharing web sites and web sites specialising in video, for example YouTube, they are becoming increasingly popular. Web Cams are increasingly used in communications with other users.

 

 

 

What you have to do!

Watch the videos above and in your Word document or your Brain complete the following exercises.

1. Why is a track pad suitable for controlling the pointer on a laptop?

2. Why do you think the combination of a keyboard and mouse is used as a means of inputting data into a desktop?

3. Describe a graphics tablet.

4. Who uses a graphics tablet?

 

 

What you should be able to do!

1. Explain why computer systems need Input Devices.

2. Provide a number examples of input devices.

3. Recommend a selection of input devices system for a variety of situations..

 

Continue to 4. Input Devices: Cameras