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14 Cards in this Set
- Front
- Back
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Keyboard
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Most commonly used input device; made up entirely of keys that are grouped; QWERTY keyboards are the most common, and is named because of the first 6 letters.
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Mouse
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Along with a keyboard it is a very common input device. Mice normally have two buttons and a scroll wheel. The left button lets you click things on your screen. The right button lets you open a menu with relevant options in it. Modern mice use 'optical' technology.
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Touchpad
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Touch-pads are only ever really found in laptops, mainly because laptops are portable and so mice cannot always be used. You drag your finger over it and it will move the mouse. There are two buttons to replace the left and right mouse buttons.
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Joystick
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Joysticks were originally used by pilots in their planes, however computer gamers took up this idea to allow for more realistic gaming. Joysticks can be moved in many directions and it will tell the computer which one it's being moved in.
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Concept Keyboards
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A concept keyboard is just a board that has a grid of buttons; each can be programed to do whatever the user wants. An overlay sheet with pictures of text on so that the user knows what does what. Animal noise keyboards and McDonalds use these.
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Touch Screen
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This is an input and output device, your finger being the input and the screen itself being the output. A menu driven interface is perfect for this – an ATM for example. Smart phones and tablet computers make use of these.
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Scanners
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These are sometimes used to convert text/images into useable data. Light is shone onto the object being scanned, and then it is picked up by the sensor which creates a digital image of the object. Flatbed scanners are more common and better than handheld scanners.
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Graphics Tablet
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Graphics designers and illustrators often use these. Using these device designers can be much more precise than with a mouse. Talented artists can create amazing art with this and a program like Photoshop. The tablet consists of a pad that you draw on with a special pen.
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Microphone
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This inputs sound via an electrical signal that is then converted from analogue data into digital data that is stored and manipulated. Voice recognition software is now common and can be used to dictate text to a computer – not perfect yet though.
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Webcam
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This captures video footage of the scene in front of it. It is usually connected via USB or built into a computer. It captures frames (snapshots) one at a time, but it usually does about 30 per second (over 25 per second makes us see motion video). These are mainly used for seeing people via internet, tourism and security.
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Barcode Reader
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A barcode contains info about the country of manufacture, the name of the manufacturer and a product code (no price info!) The reader shines red light onto the code, it is read by this and the computer/database tell us all the info on it. Library cards also use this.
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Optical Mark Reader (OMR)
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Multiple choice tests use these lots. It scans the sheet, and detects pencil/pen marks (less light is reflected, that’s how it knows) then inputs this data into a computer. It’s faster and more accurate than using several humans, but sometimes doesn’t read the info correctly.
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Biometric Devices
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Fingerprint and retinal scanners are now used in many places, the main reason being for security/identification. Special devices capture the info; give it to computers which identify it; then tell us again. Passport control and some ATMs are good examples.
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Sensors
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Sensors detect pressure, light and temperature outside a computer. These will automatically collect this data at regular intervals then store the data, and then sends a batch of reading at once. An ADC (analogue digital converter) is required to convert the reader’s data.
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