Yahoo! Developer Network has a very interesting recommendation.
Yahoo! UI Library: Grids CSS states,
Getting Started
“You must be rendering in Standards Mode to use Grids. Many doctypes will trigger Standards Mode in the browser, but we recommend and use this one:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <!-- layouts require "Standards Mode" rendering, which the 401-strict doctype triggers -->
The Yahoo! index page follows its Developer Network Guidelines (except for lacking an external style sheet.)
However.
- Yahoo!
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
- Yahoo! Audio
<!doctype html public "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><meta http-equiv="content-type" content="text/html; charset=UTF-8">
- Yahoo! Autos
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><meta charset="ISO-8859-1" />- [Note: All meta:elements were self-closed.]
- Yahoo! Directory
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><meta http-equiv="content-type" content="text/html; charset=UTF-8">
- Yahoo! Finance
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
- Yahoo! Finance
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
- Yahoo! Games
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
- Yahoo! GeoCities
- No DocType declared
- No Content-Type declared/No Content-Encoding declared
- Yahoo! Groups
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">- No Content-Type declared/No Content-Encoding declared
- Yahoo! Hot Jobs
- No DocType declared
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
- Yahoo! Images
<!doctype html public "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><meta http-equiv="content-type" content="text/html; charset=UTF-8">
- Yahoo! Local
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><meta http-equiv=Content-Type content="text/html; charset=UTF-8">
- Yahoo! Maps
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">- No Content-Type declared/No Content-Encoding declared
- Yahoo! Movies
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">- No Content-Type declared/No Content-Encoding declared
- Yahoo! Music
- No DocType declared
- No Content-Type declared/No Content-Encoding declared
- [Note: And, in-line styles accompany external style sheets.]
- Yahoo! News
<!doctype html public "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><meta http-equiv="content-type" content="text/html; charset=UTF-8">
- Yahoo! Personals
- No DocType declared
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">- [Note: And, plenty of in-line and on-page styles.]
- Yahoo! Photos
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
- Yahoo! Real Estate
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">- No Content-Type declared/No Content-Encoding declared
- Yahoo! Search Blog
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN " "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd "><meta http-equiv= "Content-Type " content= "text/html; charset=iso-8859-1 " />
- Yahoo! Shopping
- No DocType declared
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
- Yahoo! Sports
- No DocType declared
- No Content-Type declared/No Content-Encoding declared
- Yahoo! Tech
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><meta http-equiv="content-type" content="text/html; charset=UTF-8">
- Yahoo! Travel
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"><meta http-equiv="content-type" content="text/html; charset=ISO-8859-1; lang=en-US">
- Yahoo! TV
- No DocType declared
- No Content-Type declared/No Content-Encoding declared
- [Note: Tables/Styles MischMasch Supremo]
- Yahoo! Video
<!doctype html public "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><meta http-equiv="content-type" content="text/html; charset=UTF-8">
- Yahoo! Yellow Pages
- No DocType declared
- No Content-Type declared/No Content-Encoding declared
- [Note: Tables-based.]
All HTTP Response Headers returned,
- Content-Type:text/html
- Content-Encoding:gzip
Yahoo! Developer Network recommends HTML 4.01/Strict for rendering standards mode in user agents. Therefore, if one follows the World Wide Consortium's implied use of the word "recommendation", e.g., "directive", HTML 4.01/Strict's it.
And, for them what cares,
- No DocType declared
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
