HTML DOCTYPE Document Type example description

HTML4.01 document Transition definition types, documents defined by this type can use tags and elements in HTML to include tags that are not recommended by the user (e.g., font, b, etc.), and cannot use frames

<!DOCTYPEHTMLPUBLIC"-//W3C//DTD HTML 4.01 Transitional//EN""http://www.w3.org/TR/html4/loose.dtd">

HTML4.01 documents are strictly defined types, documents of this type can use tags and elements in HTML, cannot contain labels that are not recommended by the users (e.g., font, B, etc.) and cannot use frames

<!DOCTYPEHTMLPUBLIC"-//W3C//DTD HTML 4.01//EN""http://www.w3.org/TR/html4/strict.dtd">

The HTML4.01 document framework defines the type, which is equivalent to the HTML4.01 document transition definition type, but you can use the framework

<!DOCTYPEHTMLPUBLIC"-//W3C//DTD HTML 4.01 Frameset//EN""http://www.w3.org/TR/html4/frameset.dtd">

XHTML1.0 document Transition definition types, documents defined by this type can use tags and elements in HTML to include tags that are not recommended by the user (e.g., font, b, etc.), and cannot use frames

<!DOCTYPEhtmlPUBLIC"-//W3C//DTD XHTML 1.0 Transitional//EN""http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

XHTML1.0 document strictly defined type, the document defined by this type can only use the tags and elements defined in the HTML, cannot contain tags not recommended by the list (for example: Font, b) (this type is used in the dream), the frame can not be used

<!DOCTYPEhtmlPUBLIC"-//W3C//DTD XHTML 1.0 Strict//EN""http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

The XHTML1.0 document framework definition type is equivalent to the XHTML1.0 document transition definition type, but you can use the framework

<!DOCTYPEhtmlPUBLIC"-//W3C//DTD XHTML 1.0 Frameset//EN""http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">

XHTML1.1 document strictly defined type, equivalent to XHTML1.0 document transition definition type

<!DOCTYPEhtmlPUBLIC"-//W3C//DTD XHTML 1.1//EN""http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">

HTML5 Document Type

<!DOCTYPEhtml>

Monkey tip: The tags used in the HTML declaration are very special (different from the tag syntax described earlier), using the <! Start, end without closing the character.

HTML DOCTYPE Document Type example description