Why did my son get banned on XBL?

Off course using periods is the right way to use it! Tsssskkkk...

What are periods for? To group different words together as a sentence and to separate multiple sentences from other ones. So it's used to show groups! Groups of number quantities for example:

- 1x thousand + 1x million + 1x billion = 1000.1000.1000
- 1x thousand and 1x thousand and 1x thousand = 1000 and 1000 and 1000 = 1000,1000,1000

For here now it's proven that USA citizens can't do math...

Hmmmm, I think I found the cause of the credit crisis in the USA! When you earn 3x $1000,- you don't own 1 billion...

See that long key on your keyboard with nothing (usually) on it? IT'S CALLED A SPACE BAR. You use THAT + a comma to denote a sperate item in a list ¬_¬.

I don't use commas or spaces or periods to separate my numbers. I just do this: 1000000000000. 1 quadrillion, and it's easy to write.