Indention - why spaces?

[Felix Domke]

Hi kernel hackers,

yes, i know http://www.purists.org/linux/#indent .

my question is just: what's the matter of NOT using tabs instead of 
spaces? i think there must be one, otherwise everybody would use tabs.

I know the thing about "more than 3 levels of indention *suck*" (but i'm 
not sure if i have really understand this yet in my coding style, but 
who cares..), but i like tab characters more than spaces, simply because 
it removes all the discussion about the best indention width. some 
people use ~180 character-consoles, some use 80 ones.Whats the reason of 
not giving the freedom to choose whatever he likes?

i don't want to change anything, i just like to know WHY people use 
spaces. are they somehow unportable? (i don't think so)