INPUT DEVICES

1. INPUT DEVICES Information & Communication Technology School Year 2012/2013 Manarat Jeddah International School for Girls

2. List of Input Devices

3. Keyboard • Most common input device • Used to input text, for example into a word-processed document • Also used to type commands into a computer, for example pressing the control (Ctrl) key at the same time as pressing X (to cut a selection) • Advantages • Most computer users are familiar with them/require little training • Allow accurate entry of data, in combination with a monitor to check accuracy • Allow quick entry of original text; can enter a variety of text, not limited to bar codes, OMR • Robust devices • Disadvantages • Continually typing can lead to RSI; difficult for people with disabilities to use; take up more space than other input devices; not very fast when compared to direct data entry devices such as OMR and barcode readers

4. Mouse • Pointing device that can • Select items from a menu • Left clicking will open a program or another window • Use to scroll up or down in the active window • Drag and drop • Inside the case can be a ball, which allows the mouse to glide over a surface • Optical mouse relies on movement being detected using reflected light, rather than a ball • Cordless mouse needs a transmitter and a receiver, connects via bluetooth (radio waves) • Advantages • Most computer users are familiar with them/require little training • Allow faster entry of options, compared to typing • Allow fast navigation through slideshows/websites • Smaller and more compact than keyboards • Disadvantages • Need a flat space; mice with balls can become clogged by dust and grime; overuse can lead to RSI; difficult for people with disabilities to use; difficult for entering data

5. Trackerball • Upside down mouse like device, designed for users that have disabilities; since it is stationary, it is also useful where the user has limited motor skills or there is a lack of space • There is a large ball in the middle that is controlled by using the palm of the hand and enables the user to control the pointer on the screen. • Used when the use of a mouse would be too difficult; can be used in control applications where objects on a screen are used to control a process • Advantages • Does not require the fine control a mouse does; easier for people with RSI; can be more accurate when positioning a pointer on a screen • Disadvantages • Difficult to enter data; can be slower to use than a mouse

6. Concept Keyboard • Flat board that contains a grid of buttons. Each button can be programmed to do whatever you want. • Overlay sheet with pictures or symbols is placed on the grid so that the user can tell what pressing on different areas will do • Used when fast input is needed and are ideally suited to selecting from a limited range of choices such as fast food restaurants, and for young children. • Advantages • Faster to use, and created waterproof • Disadvantages • Limited to the options shown • Poor for text input

7. Numeric Keypad • Used in ATM machines, mobile phones, when entering PIN numbers, at EPOS (electronic point of sale) terminals, if the barcode is damaged the person can key in the barcode number quickly • Advantages • Small compact and portable; easy to cover up when entering a PIN • Disadvantages • Difficult to enter text; can be too small for numbers to be used effectively

8. Chip and Pin Reader These are a type of smart card reader, but tend to be used only at EFT/POS terminals. There are a number of versions of these readers. Sometimes the chip and pin reader does not have a a magnetic strip reader. These devices have a slot for entering the chip card manually, a numeric keypad for entering the PIN and a small display to show instructions. Some of these readers have a separate magnetic strip reader across the top or side. The card cannot be used in the chip and PIN reader unless the person knows the PIN. Used anywhere a payment is required (grocery shops, etc.) The chip on a bank card contains: Card number, PIN, Expiry date, Type of card/issuer, Security number • Advantages • Chips are more robust than a magnetic strip • More secure than magnetic strip cards; quicker than cash or cheques • Disadvantages • If the customer forgets the PIN they cannot continue the transaction • The person using the card needs to make sure no one can see the PIN number as they enter it

9. Magnetic Strip Reader • Can be used anywhere a payment is made using a bank or credit card, such as: ATMs, part of Electronic Funds Transfer at Point of Sale Terminals (EFTPOS) in hypermarkets and other shops • In security, they are used to prevent unauthorised access to restricted buildings or hotel rooms • Advantages • Faster, more accurate and more secure data entry than typing on a keyboard • Disadvantages • If the strip is damaged, data has to be entered manually, resulting in loss of speed at EFTPOS terminals • If the strip is damaged or the card is lost, the holder cannot gain access to the building or hotel room

10. Smart Card Reader • The inside of a smart card usually contains an embedded microprocessor, under a gold contact pad; microprocessor is there for added security • Used in credit cards, computer security systems, mobile phones, banking, satellite TV, ID cards • Advantages • Allow immediate updating, thereby preventing fraud • More robust and secure than a magnetic stripe • Prevents entry into restricted areas without a card • Disadvantages • If the card is lost the owner could lose the value on the card • There is a lot of information on some • cards, if it is stolen, hackers can use it • for fraudulent purposes and identity theft.

11. RFID (Radio Frequency ID) • Tags are attached to objects so they can be identified through the use of radio waves. • The reader is used to transmit a radio signal in order to communicate with the RFID tag. • Outside the realm of retail merchandise, RFID tags are tracking vehicles, passports, library books, Alzheimer's patients and pets. • RFID tags are an improvement over bar codes because the tags have read and write capabilities. Data stored on RFID tags can be changed, updated and locked. • Advantages • Unlike barcode readers, they can cope with objects between the tag and the reader • They can be read from and written to; are robust and more difficult to copy than a barcode • Disadvantages • More expensive technology • When used to hold personal information, people’s movements can be tracked easily, leading to a lack of privacy

12. Scanner • Used to enter hard copy images into a computer • Can be used with OCR software • Used to obtain digital images of photographs • Used in retail stores for reading barcodes Advantages • Allow images to be stored for further editing • Quicker than typing in a barcode Disadvantages • Accuracy of reproduction is limited

13. OCR • Optical Character Recognition Software • Used after documents have been scanned in and saved to the computer, converting the image into understandable text • Text is read by scanner • Image compared with characters stored in computer • Converted to text for use with other software • USES: • Used to process passports, ID cards, car number plates and to sort mail • Also used to input data from hard copy to word processor • Also can be used by blind people to scan in documents and have them read out loud • Advantages: • Faster method of data entry; easier for people with disabilities • Disadvantages: • Lots of errors are produced; cannot read handwriting very well • Keyboard can be more accurate than OCR

14. Most items that are for sale in a shop have a barcode printed somewhere on the packaging, also used in libraries. A barcode is normally a pattern of thick and thin, dark and light lines. A form of a scanner called a barcode reader is used to read them Barcode Reader • The barcode does NOT contain the price of the item, this is held on the company database. The barcode contains the country and name of manufacturer, product code, etc. Advantages • Price changes only need to be made to the database and not every single product package • Faster and more accurate data entry than typing Disadvantages • Can be expensive, especially for smaller businesses

15. OMR (Optical Mark Reader) • Use of a reader to input data from pencil or pen marks on a form • Pencil/pen marks are read by scanner or reader • Position of marks are identified • Processing of many types of forms; for example, exam papers/school registers/lottery/multiple choice questionnaires • Advantages • Only one computer needed to collect and process data • Quick data entry; easy for the user to fill out forms • Disadvantages • If the marks don’t fill the space completely, or there is a smudge somewhere on the paper they may not be read correctly • Keyboard and OCR can input text more easily than OMR • Only suitable for recording multiple choice answers • Forms have to be designed carefully, this can be expensive • Pre printed stationery is required for OMR

16. MICR (Magnetic Ink Character Recognition) • Used in banking applications for the processing of cheques, special magnetic font used at the bottom of cheques • Cheque number; sort code; account # • Characters read by magnetic reader • Characters compared with characters stored in computer • Converted to text for entry into system • Advantages • More secure than OCR as they cannot be tampered with • More accurate method than OCR or manually inputting the information • Cheques can be read even if they have been overwritten • Disadvantages • Limit to the character set that can be used; expensive method of data entry

17. Digital Cameras • Can be connected directly to a computer and photos uploaded • Can be connected directly to photo printers • Can also take short videos • Can be used in software for image editing Advantages • Can produce better quality images than traditional • Quicker to upload images directly than scan them • Memory card can hold more images than film Disadvantages • Batteries needs frequent changing, more expensive

18. Microphones • Can be connected directly to the computer • Used to input sounds, can be stored and manipulated • Analog signal – sound card acts as an A/D converter • Used most often to input speech for a voiceover • Can be used with voice recognition software to convert speech to text Advantages • Quicker to input text by speaking than typing Disadvantages • Computer cannot be used during recording • Voice recognition software not that accurate

19. Instruments connected to a computer using a Musical Instrument Digital Interface Interface converts the output signals from the instrument into a digital form the computer can understand. MIDI Instruments • Performance can be directly recorded onto a computer and stored as a MIDI file • Musicians can use to supplement other instruments Advantages • Files can be manipulated; errors in performances can be removed Disadvantages • The music produced can sound manufactured

20. Graphics Tablet • Can be used with a stylus to input freehand work into a computer and create graphics. • The stylus (can be a pencil if paper is used) is used to draw or trace and input. • Used in East Asia to write Chinese, Japanese and other character languages (easier than typing) Advantages • More accurate way of drawing versus a mouse Disadvantages • More expensive than mice

21. Webcams • Similar to video cameras, but are connected directly to the computer • High quality webcams are used by businesses in videoconferencing Advantages • Can be online constantly; elderly people can keep in touch with people without leaving their homes Disadvantages • No storage capability, not portable, very limited features (ex. cannot zoom , no video-editing facilities)

22. Light Pen • Device that allows a user to interact with a computer display (CRT) • The light pen can be used to select items on the display or to draw on the display • Uses include retail sales in point-of-sale (POS) applications, gaming, graphic arts, and healthcare applications • Healthcare Example: Light pens are now sometimes used with ultrasonic scanners and with some nuclear medicine imaging apparatus to draw round a particular organ or region of interest seen on the display. A typical application might be drawing a line around the circumference of the fetal trunk. The computer program might then present a figure for the area contained, such as the estimated weight of the fetus, or its estimated maturity. • Disadvantages • Strain of holding the pen to a screen over time limited the use of light pens

23. Joystick • Used to play games • Used in the training of airline pilots to control various aspects of flying an aircraft • Used for controlling machines such as cranes, trucks and powered wheelchairs • Can be used to control objects in three dimensions • Disadvantages • Not particularly robust; can be difficult to control

24. Biometric Devices • Biometrics means to measure and analyze human characteristics in order to correctly identify an individual. • Examples of physical characteristics that can be used are: • Fingerprints • Voice Recognition • Retinas or irises • Facial patterns • Palm Prints • Special devices are needed to capture the biometric data which is then passed onto the computer for processing and identification.Biometric authentification methods can be used to identify you at ATMs to withdraw cash, in computer networks to allow you to log on and many schools are now introducing 'fingerprint registration'! • Advantages • Believed to be more secure because the physical characteristics are unique to every individual and cannot be stolen, copied or lost. • Disadvantages • Far from foolproof; many errors and false accepts are possible

25. Sensors • Device used to input data about physical changes in an environment that is being monitored or controlled. • Used to collect data Advantages • More reliable than humans; more accurate (no human error); can be used in places humans cannot go; readings can be taken continuously; human resources can be allocated elsewhere Disadvantages • Sensors need a power source, if they lose power, they will stop working

26. Temperature Sensor • Read the temperature of their surroundings and send the readings to the processor. • Sensors do NOTmake decisions they only collect and report data • Used in washing machines; computer-controlled greenhouses; central heating and central cooling systems; automatic cookers

27. Pressure Sensor • Measures the amount of pressure exerted and sends that information to a processor which decides what action to take, if any. • Used in burglar alarms, washing machines, robotic arms

28. Light Sensor • Measures the amount of light falling on the sensor • Used in computer-controlled greenhouses, headlights of cars, streetlights, burglar alarms

29. Analogue & Digital Signals Analogue Signal = continually changing with any value possible For example: Temp = 18.454345° C Digital Signal = discrete values; limited number of values For example: Temp = 18.5 ° C

30. ComputersDO NOT understand analogue signals Computers ONLY understand digital signals Analogue signals must be converted to digital signals via an A/D converter