Emacs default font

[bhargava]

Hi all, 
I would like to know what is the name of the default font in emacs. I
donot like the default font that comes with the ubuntu package. I used
emacs that I compiled from the source. For some reasons now I'm stuck up
with the emacs installed from the ubuntu repo. I liked the default font
that came with it. So I never cared about the font.  I read some where
about cse-huji-default-font but could not find this using the M-x
command. (describe-variable).

The font I'm talking about is some what similar to the font in this web
page http://www.gnu.org/software/emacs/tour/ .

So please let me know what the default font of emacs is how to set it. 

Thanks.