Operating System

The Operating System (OS) is a generic term that supervises application programs and all input and output functionality of the computer. An output on a monitor, keeping track of files and directories on the disk, and controlling peripheral devices such as disk drives and printers are all examples of some of the things the OS does. Without the operating system, users couldn’t interact with the computer. Windows Vista, Mac OS X, and Linux Ubuntu are examples of operating systems. All modern OS’s have similar characteristics:

Operating System Characteristics:

• User Interface
• Command Processor - (CLI or GUI)
• Job Management - Controls the order and time which programs run
• Task Management - Controls more than one program at a time; allowing multitasking
• Memory Mangement - Placement of programs and data in memory
• File Management - Involves reading, writing, or modifying data on a storage device
• Device Management - Controls hardware using device drivers

Operating System Catagories:

• Single user, Single Tasking - User does one task at a time. Uses little memory and power.
  Example: Palm OS.
• Single User, Multitasking - One user performing more than one task at a time. GUI and large storage and memory requirements.
  Example: Windows/Macintosh.
• Multi User, Multitasking - More than one user performing more than one task at a time on the same computer.
  Example: Terminal Access on a Server; UNIX.
• Realtime - Works with realtime application programs used in hardware.
  Example: Medical/Science Equipment.

Written by Clio