[tragiclos]

It's about looking at supply vs demand. Electrical devices are often labeled by the minimum voltage they require to operate. 110 V is commonly used because the device can operate reliably on a 120 V distribution system.

[darknavi]

I learned recently that Japan is often on 100V power so I'd think a lot of international components would support 100-240V.

[chociej]

It's mostly just a misnomer. A 110 V device with a 5% tolerance, for example, would not work on nominal US circuits.