1.1.3 Input, Output and storage

• What is an input device?

  A device to put data into a computer
• What is an output device?

  A device to send information from a computer
• What is the function of a keyboard?

  To enter text into a computer
• What is a webcam used for?

  A camera to take photos and record videos
• What does a magnetic stripe reader do?

  Reads data from magnetic stripes on cards
• What is the purpose of a barcode reader?

  Reads information from printed labels and cards
• What is the function of speakers?

  To output sound from a computer
• What do printers do?

  Output information onto paper
• What is the purpose of a projector?

  Projects video content onto a screen
• How does a touch screen function as both an input and output device?

  It outputs visuals and accepts touch input
• What should be considered when purchasing an input device?

  • Speed of input
  • Accuracy of input
  • Cost
  • Relevance to the task
• What are the different methods of storing information?

  • Optical storage
  • Magnetic storage
  • Flash storage
• What are optical devices used for?

  Read and write data using lasers
• How is binary information represented on optical discs?

  By reflecting or scattering laser light
• What does CD stand for?

  Compact disc
• What are CDs commonly used for?

  Storing audio files, text, and images
• What are the disadvantages of CDs?

  They are easily damaged and have limited capacity
• What is the difference between CD-R and CD-RW?

  CD-R can be written once, CD-RW multiple times
• What does DVD stand for?

  Digital versatile disc
• Why are DVDs suited for storing digital videos?

  They have a higher storage capacity than CDs
• What is a Blu-Ray disc?

  An advancement over DVDs with more storage
• How do magnetic devices represent binary information?

  Using two magnetic states: polarised and unpolarised
• What is the most common type of magnetic storage?

  Hard disk drives
• What is the typical capacity range of hard disk drives?

  Between 500GB and 5TB
• How do hard disk drives work?

  By rotating magnetic platters under a read/write head
• What are the disadvantages of hard disk drives?

  Slow transfer speeds and damage from movement
• What is magnetic tape used for?

  To record computer data
• How was magnetic tape used in the past?

  Wound onto reels and passed through readers
• What is a floppy disk?

  A thin magnetic disk enclosed in plastic
• What was the typical storage capacity of floppy disks?

  1MB, with some up to 200MB
• What is flash storage?

  Fast and compact storage using silicon semiconductors
• How does flash memory store information?

  In blocks combined to form pages
• What is the preferred logic gate for small data storage?

  NOR is preferred for small data
• What is the difference between RAM and flash memory?

  RAM is volatile, flash is non-volatile
• What are solid state drives (SSDs)?

  Popular storage with no moving parts
• What are the advantages of SSDs?

  Light, portable, and high data transfer rates
• What is a disadvantage of SSDs?

  Higher cost compared to other storage
• What is RAM used for?

  To store data and programs currently in use
• Why is RAM more expensive per gigabyte?

  It has higher access speeds than secondary storage
• What is ROM used for?

  To store fixed sequences of instructions