Operating system is a central software of the computer without which a computer cannot work. First operating system is installed in the computer and then any other software. Be it a Microsoft word, a game, or a video playing software such as Cyberlink Power DVD. Operating system provides services to these software so that they can work.
Choosing a right operating system is not a difficult task as Windows operating systems (Windows XP, Windows 7, Windows 8, etc.) are the most popular operating systems till date. New version comes with added functionality. However there are operating system editions as per user requirement.
For instance Windows XP Home was designed for Home users whereas Windows XP Professional was specifically designed for business use.