Victor Dewsbery has added a post in his blog Language Mystery going into great (and alas necessary) detail on millions, milliards, billions, trillions etc.

Translating numbers: 1. How much is a billion?

This history of the number systems has also created “false friends” for translators. A German “Billion” is not the same as an English “billion”. The words “Trillion” and “Quadrillion” are also misleading. And a German “Milliarde” is not a “milliard”.

This much I remember, and I am very grateful to Victor for setting it out so well. Take a look around for other topics while you’re there.