Apple uses Windows on iMacs on their Mac Pro production line.

Apple Mac Pro production starts in the USA, well then later the web witnessed Tim Cook’s tweet about visiting Apple’s Austin, he shared a picture that was taken along the assembly line of Mac Pro.

The production line have iMacs that provide information along the process and what do they happen to be running, but what appear to be the Windows 7 operating system!

Here is the pic, (click to enlarge)