Posted by Max Hauser
a resident of Old Mountain View
on Feb 6, 2011 at 7:28 am
Max Hauser is a registered user.

Being less accustomed to the phrase "World Expo," I checked and this article does describe what's generically (and was in the US traditionally) called a World's Fair, and more formally today a Universal Exposition. Other names also have appeared since the modern world's fairs began in 1851 in London. I gather "World Expo" is currently favored among US organizers as quoted above, though the phrase isn't universal (Wikipedia for instance contains no "World Expo" entry, redirecting to "World's Fair," first link below). Some people will remember the 1967 Montreal World's Fair (and the commemorative postage stamp that followed). That event used the proprietary and then-unique name "Expo 67" which started a trend. More history in Wikipedia:

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