Operating Systems

Operating Systems

1. functions

   • user interface
     • The part of an operating system that allows the user to enter and receive information
       • text-based user interface
         • Commands are usually typed on a command line using a keyboard
       • graphical user interface
         • Functions are carried out by clicking or moving buttons, icons and menus by means of a pointing device
   • memory management
     • The function responsible for managing the computers primary memory
       • It determines how memory is issued among computing processes, deciding which gets memory, when they receive it and how much they are allowed
   • security
     • The operating system provides authentication using:
       • Authentication: The process or action of verifying the identity of a user.
       • username and passwords
         • These are names and passwords registered with the operating system to whom it allows access at the time of login
       • key cards
         • These are physical cards programmed by the operating system with unique identifying information that allows the user to login to the system.
       • User attributes
         • The operating system registers unique physical characteristics of the user (called attributes) to identify them at login. These include fingerprints, signatures and eye retina patterns.
           • Eye retina patterns: when you get your eye scanned.
   • multi-tasking
     • It allows the user to preform more than one computer task (almost all of today's operating systems can multi-task)
   • peripheral management
     • The operating system uses programs called device drivers to manage connections with peripherals.
       • Device drivers handles the translation of requests between a device and the computer.
       • They define where a process must put outgoing data before it can be sent and where incoming messages will be stored when they are received.
       • They wake up the device when it is needed and puts it back to sleep when it's not.