Um original v�lido de HTML/XHTML declara no original que vers�o de HTML/XHTML � usada. O tipo declara��o do original nomeia o DTD (Document type definition) no uso para o original.
HTML 4.01
O HTML 4.01 especifica tr�s DTDs
DTD estrito
DTD Transitional
DTD de Frameset
Os autores devem incluir um do tipo declara��es do original em seus originais. O DTDs varia nos elementos que suportam.
DTD estrito
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">
DTD Transitional
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01
Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
DTD de Frameset
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Frameset//EN"
"http://www.w3.org/TR/html4/frameset.dtd">
XHTML 1.0
XHTML 1.0 especifica tr�s DTDs
DTD estrito
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
DTD Transitional
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0
Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
DTD de Frameset
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">
XHTML 1.1
DTD
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
"http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
Keywords:xml document, xml schema, w3c xml schema, xml parser
