Definition from Wikipedia[.]com

An operating system (OS) is a collection of software that manages computer hardware resources and provides common services for

computer programs. The operating system is an essential component of the system software in a computer system. Application programs usually require an operating system to function.

Time-sharing operating systems schedule tasks for efficient use of the system and may also include accounting software for cost allocation of processor time, mass storage, printing, and other resources.

For hardware functions such as input and output and memory allocation, the operating system acts as an intermediary between programs and the computer hardware, although the application code is usually executed directly by the hardware and will frequently make a system call to an OS function or be interrupted by it. Operating systems can be found on almost any device that contains a computer—from cellular phones and video game consoles to supercomputers and web servers.

Examples of popular modern operating systems include Android, BSD, iOS, GNU/Linux, OS X, QNX, Microsoft Windows, Windows Phone, and IBM z/OS. All these, except Windows and z/OS, share roots in UNIX.


So... Which operating system (OS) is my device using?

The sentence displayed in red below is your current operating system together with your browser information.




E.g. If the information shown above is Mozilla/5.0 (Windows NT 5.1; rv:23.0) Gecko/20100101 Firefox/23.0

Hence, the Windows NT 5.1 indicates your device's operating system is Windows XP.


Table below is for your kind reference.

Information Display Your Operating System
Win16 Windows 3.11
Windows 95 or Win95 or Windows_95 Windows 95
Windows 98 or Win 9x 4.90 or Windows ME Windows ME
Windows 98 or Win98 Windows 98
Windows NT 5.0 or Windows 2000 Windows 2000
Windows NT 5.1 or Windows XP Windows XP
Windows NT 5.2 Windows Server 2003
Windows NT 6.0 Windows Vista
Windows NT 6.1 Windows 7
Windows NT 6.2 Windows 8
Windows NT 4.0 or WinNT4.0 or WinNT or Windows NT Windows NT
Ubuntu Ubuntu
Android Android
Linux or X11 Linux
iPhone iPhone
iPad iPad
Mac_PowerPC or Macintosh MacOS
QNX QNX (BlackBerry)
OS/2 OS2