What Windows OS am I running?

To find out what version of Windows your computer has, find the "My Computer" icon on the desktop.

Right-click on "My Computer", and left-click on "Properties".

In the "System Properties" window, click the "General" tab, and look for the area labeled "System". Right below that you should see "Microsoft Windows" and a version number. In this example, it says "Microsoft Windows 2000".
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What MacOS am I running?

All Macs have an "Apple" menu in the upper-left-hand corner of the screen. To determine the version of MacOS that you are using, click on the desktop, then go to the Apple Menu, and select "About This Macintosh", "About This Computer" or "About This Mac".

You will then be presented with a window that looks like one of the above. The MacOS version number will be in the top-right-hand corner of the window for all versions from 7.6 to 9.x. In MacOS X (10), the version number is centered near the middle of the window.
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