Computer studies

• Computer System


  Components that make up a computer system
• Storage


  • Stores files/programs
• ROM (Read Only Memory)


  • Instructions to start computer up are stored here. Files not lost when power off.
• CPU (Central Processing Unit)


  Brain of the computer. Carries out all of the instructions required for programs to run.
• RAM (Random Access Memory)


  • Stores files and programs which are currently being used
• Storage (Hard Disk Drive)

  • Stores files and programs which are not being used. Files are not lost when power switched off.
• Storage Capacity - Units

  • Bit
  • Nibble
  • Byte
  • Kilobyte
  • Megabyte
  • Gigabyte
  • Terabyte
  • Petabyte
• Bit


  A single 1 or 0
• Nibble


  4 bits
• Byte


  8 bits
• Kilobyte


  1000 bytes
• Megabyte


  1000 kilobytes
• Gigabyte


  1000 megabytes
• Terabyte


  1000 gigabytes
• Petabyte


  1000 terabytes
• Input/Output/Storage Devices


  • Input Devices
  • Output Devices
  • Secondary Storage
  • Cloud Storage
• Input Devices


  A hardware device used to put data/instructions into a computer (e.g. mouse, keyboard, microphone)
• Output Devices


  A hardware device that receives data from a computer (e.g. monitor, printer, speakers)
• Secondary Storage


  A hardware device that stores data permanently
• Cloud Storage


  An off-site location to store your files. E.g. OneDrive, iCloud. You need the internet to access the files.