There are 8 types: 1. HTML5 version; 2. HTML 4.01 strict version; 3. HTML 4.01 transitional version; 4. HTML 4.01 framework version; 5. XHTML 1.0 strict version; 6. XHTML 1.0 transitional version; 7. XHTML 1.0 framework version; 8. XHTML version 1.1.
The operating environment of this tutorial: Windows 7 system, HTML5 version, Dell G3 computer.
The declaration is placed first in the document, before the tag. The
declaration is not an HTML tag; it is used to tell the web browser which version of HTML is used for the page.
Common DOCTYPE declaration
HTML 5
<!DOCTYPE html>
HTML 4.01 Strict ( Strict)
This DTD contains all HTML elements and attributes, but does not include presentational or obsolete elements (such as font). Framesets are not allowed.
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
HTML 4.01 Transitional
This DTD contains all HTML elements and attributes, including presentational or obsolete elements (such as font). Framesets are not allowed.
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
HTML 4.01 Frameset
This DTD is the same as HTML 4.01 Transitional, but allows the use of frameset content.
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Frameset//EN" "http://www.w3.org/TR/html4/frameset.dtd">
XHTML 1.0 Strict
This DTD contains all HTML elements and attributes, but does not include presentational or obsolete elements (such as font). Framesets are not allowed. The structure must be written in standard format XML.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
XHTML 1.0 Transitional
This DTD contains all HTML elements and attributes, including presentational or obsolete elements (such as font). Framesets are not allowed. The structure must be written in standard format XML.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
XHTML 1.0 Frameset
This DTD is the same as XHTML 1.0 Transitional, but allows the use of frameset content.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">
XHTML 1.1
This DTD is the same as XHTML 1.0 Strict, but allows you to add modules (such as ruby support for East Asian languages).
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
Recommended tutorial: "html video tutorial"
The above is the detailed content of There are several types of html doctypes. For more information, please follow other related articles on the PHP Chinese website!
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