What is an Operating System?

An operating system or simply an OS is a software program that enables the communication and operation of the computer hardware and computer software. Without the operating system, all components of a computer such as hardware and software will be useless and a computer without an OS is just a dumb metal. In other words, an OS describes a software program, which designed to run all other software programs on a computer. In a pure techie perspective, the OS is the backbone of a computer, which manages both hardware and software resources. The OS is comprised of system software and all the fundamental files a computer needs while booting. Devices such as   desktop computer, laptop, tablet and a smartphone use an OS that facilitates the basic functionality that the device needs while startup.

Operating SystemsThe most common operating systems includes the Windows family of operating systems developed by Microsoft, the Macintosh OS from Apple and the UNIX family of operating systems and many other special purpose operating systems that are used with mainframes, robotics, real-time control systems, manufacturing etc. (Read difference between Windows and Linux) Each OS may be different, but they all provide GUI or graphical user interface, which has a desktop and the capability of files and folders management.


Mobile Operating Systems

Similar to computers, the mobile devices like tablets and smartphones also has operating system that provides GUI and other functionalities to run various applications. The common mobile operating systems include iOS [Apple I pads], Android [Android Phones], Symbian and Windows Phone. These operating systems developed for portable devices that use touchscreen input.Unlike the earlier mobile OSes, the recently developed mobile OSes have come up with advanced features found in desktop computers.The recent OS versions use a GUI that employ pointing devices such as mouse for taking input. The mobile OSes helps the users to watch movies, play games, and browse on the net, managing calendar and many more.


Types of Operating Systems

There are different types of operating systems such as multi-user, multi-tasking, multi-threading, multi-processing, and real-time operating systems. A multi-user OS allows multiple users to run applications at the same time. This OS is used for less number of people say a group of hundred people. However, some multi-user Operating systems allow thousands of people to run applications simultaneously. A multi-tasking OS allows its users to run multiple programs at the same done. Multi-threading OS enables the users to run various parts of a program known as threads to be used at the same time. Multi-processing operating system allows a single program or process to run on multiple CPU’s at the same time. A real-time OS is designed to enable computers to respond and process inputs instantly. Typically an RTOS has very limited user interface capability and it doesn’t have any end user utilities.


Functions of Operating Systems

In a simplest level, an OS performs mainly two functions:

  • Manages the hardware as well as software resources of any system in which the OS resides. Such resources in a desktop computer are – CPU, memory [RAM, ROM], disk space and that of a cellphone are – the display screen, keypad, address book etc.
  • Enables the applications to deal with the hardware in a consistent and stable way without knowing entire details of the hardware.

The most important function of OS is managing the hardware and resources, where various input methods and programs compete with each other to achieve the CPU attention, demand storage, memory and I/O bandwidth etc. Here the OS ensures that every application gets necessary resources while keeping the other applications nicely and also the processes are running fine for all users. The second task is where a consistent API [application programming interface] is provided .Here it is important to have multiple computers using the same type of OS or an OS that is open to any changes to the hardware. A consistent API helps a software developer to create an application that runs on different types of computers with varied memory or storage space. An OS ensures the different applications continue to run in case of a hardware upgrade or a security patch updates. This is how an OS manages both the hardware and software resources of a computer.


Since the OS is the fundamental user interface for a computer, it definitely affects how you interact with the devices. Because of this people may set their own preferences for selecting a specific OS for their perusal. Say for example one user may prefer using Linux or BSD where the other person may opt for Windows 7 or any other version from the windows operating system family. A mobile user may choose an Android phone or smartphone instead of an iPhone that runs on iOS. Depending on the capacity of an application to run on multiple platforms it is important to choose an OS accordingly when you purchase a computer