Operating System

• What is an operating system?


  The operating system is the most important program that runs on a computer.
• What are some basic tasks performed by operating systems?

  Recognizing input from the keyboard, sending output to the display, and controlling peripheral devices.
• How does an operating system function like a traffic cop?


  It ensures that different programs and users do not interfere with each other while running simultaneously.
• What is one of the responsibilities of an operating system regarding security?

  Ensuring that unauthorized users do not access the system.
• What are the classifications of operating systems?

  • Multi-user
  • Multiprocessing
  • Multitasking
  • Multithreading
  • Real-time
• What does a multi-user operating system allow?

  It allows two or more users to run programs at the same time.
• Name three examples of multi-user operating systems.

  Linux, Unix, and Windows 2000.
• What does multiprocessing support?

  Running a program on more than one CPU.
• Name three examples of multiprocessing operating systems.

  Linux, Unix, and Windows 2000.
• What does multitasking allow?

  More than one program to run concurrently.
• Name two examples of multitasking operating systems.

  Unix and Windows 2000.
• What does multithreading allow?

  Different parts of a single program to run concurrently.
• Name two examples of multithreading operating systems.

  Linux and Windows 7.
• What is a real-time operating system?

  An operating system that responds to input instantly.
• Why are general-purpose operating systems like DOS and UNIX not considered real-time?

  Because they do not respond to input instantly.
• What role do operating systems play for application programs?

  • Provide a software platform for applications to run
  • Applications must be written to run on a specific operating system
  • Choice of operating system affects available applications
• What are the most popular operating systems for PCs?

  DOS, OS/2, and Windows.
• What is another operating system available besides the most popular ones?

  Linux.