SGML/HTML parser

hi,

It seems to me that we only need one SGML parser or
HTML parser in our web application, so why are there
both SGML parser and HTML parser in W3C lib?

thanks.
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Tao Jiang     Visiting Engineer,               E40-369, CECI, MIT
phone:        (617)-253-3514(o)  (617)-576-9665 (h)
email:   jiangt@ceci.mit.edu    URL:  http://www.mech.pku.edu.cn 
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