Million and billion

a million = 1,000,000
a billion = 1 000 000 000 (in America)
In UK, a billion is a million million, I think. (SO add 3 more zeros)

I think these words are just like "thousand" and "hundred".

eg.

Five hundred and fifty people attended the lecture.
Hundreds of people attended the lecture.

Maybe someone else has a better explanation.

Is it safe to say:
"billions of years"
"millions of people"?

Hi Anne,

Yes, I think so.

"six million people"

as opposed to

"millions of people"

I'm Spanish and I'm just a student, but I've been taught that although "billion" used to be 1,000,000,000,000 in BrE, it's not like this anymore. The difference no longer exists and billion is now 1,000,000,000 in both BrE and AmE. Not sure if this is true, however...

Historically 'billion' was a word coined by French arithmetician Chuquet in 1484 to denote 'million millions' or '(10^6) x (10^6) =10^12'. Chuquet's counting system was adopted by John Locke in 1690. But in France, during the Revolution, some arithmetician proposed to reform the Chuquet system, and in the new system 'billion' was used as a word meaning 'thousand millions' or '(10^3) x (10^6) = 10

Thanks to all!