1. By Shreya Mozumdar 6B

2.  An operating system (OS) is a program that, after being loaded onto the computer, manages all the other programs on the computer.  The other programs are called applications or application programs.  The applications use the operating system by making requests for services.  The users can interact directly with the operating system using a command language or graphical user interface (GUI).

3.  Operating Systems manage the hardware and software of a computer.  On a desktop computer, it manages the processor, memory, disk space, etc.  On a cell phone, it manages the keypad, screen, address book, phone dialer, battery and network connection.  It provides a stable, consistent way for the applications to use the hardware without having to know all details (of the hardware).

4.  There are four kinds of operating systems and the first one is RTOS or real-time operating system.  This operating system is used to control machinery, scientific instruments, etc.  The RTOS operates in such a way that an operation takes the same amount of time each time it occurs.

5.  This operating system is designed such that a user can effectively do one thing at a time.  The Palm OS, or palmtops are some examples of single user, single task systems.

6.  Nowadays people use this system on their computers.  This allows a single user to have many operations on at the same time.  Some examples are Microsoft Windows and Apple Mac OS.

7.  This operating system allows many users to access the computer’s resources together.  The system must make sure that the requirements of the users are balanced, and that the programs they are using are sufficient and separate, so that a problem with one of the users does not affect the others using the system.  Some examples are UNIX, VMS and MVS.

8.  DOS – Disk operating System  One of the earliest Operating Systems and was not very user-friendly.  Windows - Managed by the Microsoft Corporation  It is user-friendly and introduced WIMP:  Windows  Icons  Menus  Pointing Device (mouse)  Mac OS – A product of Apple’s Macintosh.  Linux – Created and maintained by computer programmers worldwide.

9.  This is an open-source OS, meaning it’s code is publicly available.  It is run by computer programmers around the world.  It is free for use.  Firefox and Android are based on Linux.  Linux cannot run applications like iTunes and Photoshop.

10.  Considered to be one of the finest computing platforms.  It has a range of innovative visual features that make it attractive:  ‘Floating Dock’ instead of static start menu  ‘Spotlight’ which allows search for files and documents.  ‘Expose’ function allows user to see all the open windows at once  ‘Quick look’ lets users preview a video, PDF, or spreadsheet without opening it.  Mac OS works only on Apple computers and this limits its use.  It is normally used on individual work stations and not for entire networks.

11.  Dominates the home computer market.  Large office networks often use Windows and Microsoft Office for their operations.  Windows 7 and Windows 8 are highly user-friendly and popular.  Windows can be installed on a wide variety of computers making it the most widely used OS.

13. DOSLinuxMacintoshWindows Not user-friendlySomewhat user- friendly Highly user-friendly Based on commands Both commands and graphical user interface (GUI) Highlight is its superior GUI Has excellent GUI Not popularPopular among Computer programmers Popular as individual work stations Most popular in homes and office networks --------Open-sourceRun and maintained by Apple Run and maintained by Microsoft -------Usable on any computer Only on Apple computers Any computer ----------Free for useCostly

14.  As a home user, I will choose Macintosh as my Operating System.  I would choose it because it has extremely attractive and very user-friendly features.

15.  : http://whatis.techtarget.com/definition/operating-system-OShttp://whatis.techtarget.com/definition/operating-system-OS  http://computer.howstuffworks.com/operating-system2.htm http://computer.howstuffworks.com/operating-system2.htm  http://computer.howstuffworks.com/operating-system3.htm http://computer.howstuffworks.com/operating-system3.htm  http://www.calvin.edu/~rbobeldy/tutorials/os/basics.htm http://www.calvin.edu/~rbobeldy/tutorials/os/basics.htm  http://www.nashnetworks.ca/pros-cons-and-costs-of-operating-systems.htm http://www.nashnetworks.ca/pros-cons-and-costs-of-operating-systems.htm  http://www.scribd.com/doc/12826411/Types-of-Operating-System http://www.scribd.com/doc/12826411/Types-of-Operating-System  http://smallbusiness.chron.com/five-common-operating-systems- 28217.html http://smallbusiness.chron.com/five-common-operating-systems- 28217.html  http://www.telegraph.co.uk/technology/google/8187962/Google-Chrome- comparison-of-operating-systems.html http://www.telegraph.co.uk/technology/google/8187962/Google-Chrome- comparison-of-operating-systems.html  http://www.geek.com/desktop-computer-buyers-guide/operating-system/ http://www.geek.com/desktop-computer-buyers-guide/operating-system/