how to use system fonts?

[Michael Na Li <lina@u.washington.edu>]

I've read the relevant docs (mfonts.pdf, etc) but still can't figure out how
to switch fonts in context.

In LaTeX, I just use \usepackage{times} or \usepackage{utopia} to switch fonts
(just the basic ones came with tetex).  I expect something similar in ConTeXt
but that is not the case.

This compiles but doesn't have any effect on fonts, (unknown variant times and
utopia).

\setupbodyfont[times]
\starttext
This is roman, {\bf bold}, {\it italic}, {\bi bold-italic},
{\tfa bigger} and {\tfx smaller}.

\switchtobodyfont[utopia]
This is roman, {\bf bold}, {\it italic}, {\bi bold-italic},
{\tfa bigger} and {\tfx smaller}.
\stoptext

If I follow the instruction on 

    http://home.salamander.com/~wmcclain/context-help.html

and I can create some type-x.tex file for the fonts, like

\usetypescriptfile[type-charter]
\usetypescriptfile[type-utopia]
\usetypescript[Charter]
\usetypescript[Utopia]
\setupbodyfont[MyCharter]
\starttext
This is roman, {\bf bold}, {\it italic}, {\bi bold-italic}, 
{\tfa bigger} and {\tfx smaller}.

\switchtobodyfont[MyUtopia]
This is roman, {\bf bold}, {\it italic}, {\bi bold-italic}, 
{\tfa bigger} and {\tfx smaller}.
\stoptext

But shouldn't those typescripts be already set up?  I'm not installing new
fonts here.  I can see the names 'times', 'helvet', 'palatino' etc in the
system type-*.tex file and those files are read during the compilation.  How
can I use them?

I have 

\usetypescript [map] [default,\defaultencoding] 
\usetypescript [berry] [\defaultencoding]

in my $TEXMF/tex/context/user/cont-sys.tex file.

Thanks,

Michael

-- 
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Michael Na Li                               
Email: lina@u.washington.edu
Department of Biostatistics, Box 357232
University of Washington, Seattle, WA 98195  
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