How to check the operating system installed on your computer?

Here is the answer

Follow these steps to check the operating system installed on your computer:

1. Click “Start” and go to “Run” to launch the “Run” window.
Or
Press the “Windows” and “R” keys at the same time to launch the “Run” window.

2. Type the following on the “Run” window and click “Ok” button:

Winver

I’ve added the screen shot here.

3. You will see the “About Windows” dialog box on your screen, the operating system will be listed on this dialog box.
I’ve added the screen shot here.