Is there a reason *preset* font sizes are in multiples of 2?

[screw3d]

...with the exception of size 9.

I'm wondering why all the programs uses multiples of 2 for font sizes?

Is it one of the rules of typography or is it just the way it is??

 

[Anubis]

you can manually input whatever you want you do know that

 

[NutBucket]

Yeah, I used to use 11 and 10.5 all the time in HS to meet length limits

 

[screw3d]

I know that. Just wondering if it means anything

 

[Chronoshock]

Everyone knows that odd font sizes cause paper jams...

 

[thirdlegstump]

A lot of fonts sizes are in multiples of 2 except for the odd ones.

 

[kranky]

It keeps the drop-down menu to a manageable size.

 

[tallest1]

because 7 8 9