Input Devices Flashcards
Input device
Hardware device, which allows user to enter data into a computer
Hardware
The physical components of a computer
List 5 input devices
1) Keyboard
2) Mouse
3) Scanners (2D/3D)
4) Barcodes
5) QR-codes
How does a physical keyboard work?
When a key is pressed, an electronic signal goes to a computer. The computer processes the input and gives an output
How does a virtual keyboard work? (on mobile)
When the specific areas are pressed the output is triggered
List 2+ and 1- of a keyboard
+ Easy to use
+ No need for specific software and knowledge
- Takes lots of space
Mouse
It controls the pointer on the screen. Usually has 2 buttons and a scroll wheel. Older mice had a roller ball. Now a laser is being used
List 2+ and 1- of a laser mouse
+ Easy to use
+ No need for specific software and knowledge
- Smooth, not glass surface is needed
2D scanners
Used to scan physical documents and convert them into a digital format. The light source moves down the document and the reflection is captured. The captured image reflects onto several mirrors, convert it, send to the computer
List 1+ and 1- of a 2D scanner
+ Good quality image
- Take lots of space
3D scanners
Scan 3D objects, can be printed on a 3D printer. The scanner uses the reflection of the light or the X-rays to create a model
Where can 3D scanners be used? (1)
Airport security
When were barcodes developed?
1970s
Barcode
Illuminates the bars and the reflection is received as analog and converted into digital. Processes by a computer
List 1+ and 1- of a barcode
+ Very efficient way of finding info about the product
- Code damaged or not in the database it wouldn’t be read
QR codes
Can store bigger amount of characters than the barcode. Anyone can make a QR code and scan it
What do the big squares around the QR code tell?
Where the QR ends
List the things a barcode can contain? (5)
1) Text
2) Links
3) Contacts
4) Images
5) SMS or Email
List 3+ and 1- of a QR code
+ If it is slightly damaged, still can be read
+ More efficient in storing data than Barcodes
+ Can be scanned without a database
- Not popular
CAD
Computer aided design
OCR - how?
Optical character recognition, a process where scanned document is recognised and converted to inputs
OMR - how?
Optical mark recognition, a process where scanned marks on a page are automatically converted into inputs
Biometric device
A device, which recognises human physical characteristics
Give examples of a human physical characteristic (3)
1) Finger print
2) Iris
3) DNA
