1.5. Systems Software

• What are the types of software?


  • Systems software
  • Application software
• What is a systems software?


  Software that controls computer hardware - it provides interface between hardware and user, such as an operating system.
• What is an application software?


  Software that allows user to carry out useful tasks, for example, a word processor is an application software.
• What is the purpose of an operating system?


  To provide an interface between user and hardware - it hides the complexity of the hardware from the user.
• What are the management responsibilities of an operating system?


  • Memory management
  • Peripheral management
  • File management
  • User management
• What are the functions of an operating system?


  • Multi-tasking
  • User interface
• What is multi-tasking?


  Running many processes at the same time - OS queues processes and each one is given a small amount of CPU time before it goes to the back of the queue.
• What is user interface?


  Supplied by the OS, it is how the user interacts with the OS.
• What are some examples of user interfaces?

  • GUI (graphic-based)
  • Command line (text-based)
• What is memory management?


  OS allocating right amounts of RAM to programs as you open them and deallocating RAM when programs are closed (deals with VM if used)
• What is peripheral management?


  OS checking if devices are working, enabling or disabling them, updating drivers needed to communicate with OS.
• What are peripherals?


  Pieces of hardware that are not directly connected to the CPU, such as keyboards and printers.
• Why are peripheral drivers needed?


  They turn generic OS signals into ones hardware devices understand.
• What is file management?


  OS organising where files are stored long term so you can find them later - allows you to name, move, and save files and folders.
• What is user management?


  OS allowing you to log in with username and password and gain access to rights - allows many accounts for the same computer.
• What are utility software?


  Software that carry out one of two specific tasks designed to keep the computer running well - monitors and maintains the system.
• What does compression do?


  Reduces the size of files making them smaller to store and send.
• What does encryption do?


  Scrambles data with a key so it can only be understood with a decryption key (does not necessarily stop the data from being stolen)
• Explain defragmentation:


  As files are saved and deleted, gaps are left on the hard drive, and new files may not fit into the spaces left, so they are split into parts and saved across many small gaps - to prevent this, defragmentation rearranges files stored so no files are split up, making files quicker to access.