Font size matching

Hi all...
Seems to me that fonts are an entity unto themselves! I found there is a 
  big difference in how much space different fonts use, even though they 
are the same size. Can someone explain why some fonts are tiny at any 
given size, and take up less space then others of the same size?
And, is there a way of knowing how big they will be without doing sample 
text?

Thanks!~
John

One very simple rule: the point size of any font is the minimum line 
spacing that can be used before collisions will occur between the lowest 
descenders of the highest line and the tallest characters INCLUDING 
ACCENTS. For instance many fonts would have the tallest character as
"Â" 
(A circumflex) or Ê (E circumflex) and probably the lowest descender as 
the "g" -- or in some "artsy" fonts a "k" or a
"Q" (yes, upper case Q in 
some fonts can hang extremely low).

I have some fonts in which the highest character is a lower case "h".

JohnnyJomp wrote:
> 
> Hi all...
> Seems to me that fonts are an entity unto themselves! I found there is a 
>  big difference in how much space different fonts use, even though they 
> are the same size. Can someone explain why some fonts are tiny at any 
> given size, and take up less space then others of the same size?
> And, is there a way of knowing how big they will be without doing sample 
> text?
> 
> Thanks!~
> John
> 

JohnnyJomp:
> Can someone explain why some fonts are tiny at any 
> given size, and take up less space then others of the same size?

It is (or was) the case that monospaced fonts include linespacing 
in the point size and proportional fonts do not. So the latter 
show up taller than the former.
-- 
Good wishes!
Roy Lewis
C_Tech volunteer
(UK)