'alt vs option': Is the 'option' key still used somewhere? Where exactly (geographically)?
Images from Apple KB - How to identify keyboard localizations

US Keyboards say  alt
Option   



Other keyboards say   alt
⌥   



Basically, it's one &amp; the same key.  

Best guess is there are so many people who know Alt is but don't know Option that the terms have just merged over the years.

I haven't had a keyboard in at least a decade that actually said Option, though I remember they all did back in the 90s.

I found this 'keyboard history' article from 2007 - though it's not the main topic, it is mentioned - How Apple Keyboards Lost a Logo and Windows PCs Gained One


  Mac Integration with Windows.
  As it became increasingly useful for Mac users to emulate Windows or work in shared environments, the Option key on Macs became equated with the Alt key on PCs, and the Command key was associated with the ineffectual Windows Start button.


** After comments &amp; other answers
It appears that the Apple have changed the keyboards over the years since they made the keyboard layout page, but not updated the page to cover every current keyboard.
The answer is still really it depends - some do, some don't, in every conceivable combination ;)