Module 1.2

Cards (60)

  • an input can provide the running software with instructions and also can be data that must be processed
  • images and photos are important in the way people use the computers
  • image quality is important because when it comes to using technology we have to create digital images
  • digital cameras come in wide variety of sizes and prices with also a wide variety of features. They range from:
    smartphone cameras
    digital cameras
    top end digital single lens reflex(DSLR)
  • difference between point-and-shoot and DSLR is that DSLR have interchangeable lenses and point and shoot doesn't
  • advatages of digital cameras:
    1. able to see pictures quickly
    2. able to transfer and edit pictures
    3. can record video
    4. takes many photos
  • disadvantage of digital camera:
    1. costly
    2. qualities don't come out good
    3. difficult to take pictures in low light
  • lenses: large lenses capture more light and can imrprove image quality
  • sensor size is the size in micrometers of the sensor. We have larger sensors that can capture light more efficiently and can take photos accurately in different light conditions. A camera with large sensors produces better image quality. 15 megapixel DSLR creates better images
  • Optical zoom uses lenses on camera to get closer to the object being photographed whereas digital camera is using a magnifying glass tool to get closer to the object photographed which makes the image blurry
  • Resolution is the total number of pixels that make up an image. Specification is around 10-30Mp(megapixels)
  • ISO rating is how sensitive the camera is to light. The higher the number the more it is to light
  • a scanner is an input device that scans an image and converts it to a digital format
  • qualities of an image is produced by a scanner determined by the resolution of the scanner
  • resolution is determined in dpi (dots per inch)
    1. the greater the dpi the higher the number of pixels in the resulting image and the better the quality of the image
    2. higher the dpi higher the resulting image file will be
  • colour depth refers to the number of bits used to represent each pixel in an image.
  • the higher the colour depth the larger the resulting file size and the more memory it will take up
  • RFID: radio frequency identification, a method for tracking goods by means of tags which transmit a radio signal.
  • OCR: Optical Character Recognition - a method of converting printed text into digital text
  • advantages of scanners:
    1. can scan documents that contain text
    2. barcode scanners are useful in Point of sale to speed checkout process
    3. scanned copies can be emailed instead of being faxed
    4. QR codes can be a quick way to let people connect to your website without typing web address
  • Disadvantages:
    1. scanning can take time
    2. quality of digital image depends to a large extent on quality of original copy
  • biometric input involves capturing unique biological features of a person. involves the use of a biometric devices to recognize the persons fingerprint and iris of their eye
  • advantages of biometric:
    1. security, it is more secure than typing your password because it could be too short or based on your personal info like birthday which is obvious for people to hack
    2. biometric isn't easy to copy because everyone has different fingerprints and eyes
  • Disadvantage of biometric:
    1. its expensive
    2. sometimes it could decide not to work and glitch
    3. it needs additional hardware and software
  • the ATM gets its input from the user (PIN, language choice etc.) through the keyboard
  • a card reader is made to insert a card into a computer to read data on the magnetic strip on the card
  • ATM can communicate with your bank to withdraw money from your account, and can also send money to another account.
  • money counter: ATM uses sensors to count the number of notes it gives you so it doesn't pay too much or to little money.
  • advtanges of ATM:
    1. allows for bank transactions at any time of the day/night
    2. you can use the facilities of any banks ATM
    Disadvantages:
    1. Can be dangerous to use an ATM because of criminals
    2. can add a skimmer and camera so they can capture your card details and Pin
  • a touch screen is an input because it takes information to the computer and it is a device that allows you to interact with the computer
  • advantages of a touch screen would be:
    1. allows for more screen space
    2. very little training
    3. allows input like gestures
    Disadvantages:
    1. is not as fast as typing the keyboard
    2. can become dirty
  • POS stands for point of sale system, which is a computer system that records the sale of goods and services. ot deals with barcodes and RFID
  • RFID (radio frequency identification) is used when there are no line of sight between the reader and tag
  • The goal for POS: barcodes and RFID work faster, better stock control and more efficient
  • advantages of POS:
    1. faster
    2. can record the amount of stock left
    3. more accurate as prices are easily updated
    Disadvantages:
    1. expensive equipment
    2. needs software
    3. difficult to function offline
  • the accelerometer allows to change the orientation
  • microphone gives a command to control smartphone
  • output provides the user with feeback and information about the system and its performance and alllows transmissions of data to and from the system
  • displaying devices comes in sizes and shapes and can allow us to interact with the program
  • advantages of displaying a device would be:
    1. allowing interaction between users
    2. provides feedback to users about what happened to the computer
    Disadvantages:
    1. eyestrain
    2. not permanent
    3. expensive
    4. quality must relate to size