ๅพๆนไบๆใขใผใใจๆจๆบใขใผใใ็่งฃใใ
ใใคใฆใฆใงใใงใฏใใใ 2 ใคใฎใใผใธใงใณใฎใใผใธใไฝๆใใฆใใพใใใใฒใจใคใฏ Netscape Navigator ๅใใใใใฒใจใคใฏ Microsoft Internet Explorer ๅใใงใใ W3C ใใฆใงใๆจๆบใไฝๆใใใจใใใฆใงใไธใฎใปใจใใฉใฎๆขๅญใตใคใใฎ่กจ็คบใๅฃใใใใใใใฉใฆใถใผใฏใฆใงใๆจๆบใๆก็จใๅงใใใใจใใงใใพใใใงใใใใใฎใใใใฉใฆใถใผใฏใๆจๆบใซๆบๆ ใใๆฐใใใตใคใใจไปฅๅใฎๅคใใตใคใใๅบๅฅใใฆๆฑใใใใซใ2 ใคใฎใขใผใใๅฐๅ ฅใใพใใใ
ใฆใงใใใฉใฆใถใผใฎใฌใคใขใฆใใจใณใธใณใงไฝฟ็จใใใใขใผใใฏใๅพๆนไบๆใขใผใ (quirks mode)ใ้ๅฎๅพๆนไบๆใขใผใ (limited-quirks mode)ใ้ๅพๆนไบๆใขใผใ (no-quirks mode) ใฎ 3 ็จฎ้กใซใชใใพใใใๅพๆนไบๆใขใผใใงใฏใใฌใคใขใฆใใฏ Navigator 4 ใ Internet Explorer 5 ใฎๅไฝใใจใใฅใฌใผใใใพใใใใใฏใใฆใงใๆจๆบใๅบใๆก็จใใใๅใซๆง็ฏใใใใฆใงใใตใคใใซๅฏพๅฟใใใใใซไธๅฏๆฌ ใงใใ้ๅพๆนไบๆใขใผใใงใฏใHTML ใ CSS ใฎไปๆงๆธใงๆธใใใฆใใ้ใใซๅไฝใใพใ (ใใฎใใใซๆๅพ ใใใฆใใพใ)ใ้ๅฎๅพๆนไบๆใขใผใใงใฏใใใๅฐๆฐใฎไบๆๅไฝใๅฎ่ฃ ใใใฆใใพใใ
้ๅฎๅพๆนไบๆใขใผใใจ้ๅพๆนไบๆใขใผใใฏใใใใใใๆบๆจๆบใใขใผใใพใใฏใๅฎๅ จๆจๆบๆบๆ ใใขใผใใจใๅผใฐใใพใใใใใใฎๅๅใฏใๅไฝใๆจๆบๅใใใใใๅคๆดใใใพใใใ
ใใฉใฆใถใผใๅฉ็จใใใขใผใใๆฑบๅฎใใๆนๆณ
HTML ๆๆธใซใคใใฆใฏใใใฉใฆใถใผใฏๆๆธใฎๅ ้ ญใซใใ doctype ใไฝฟ็จใใฆใๅพๆนไบๆใขใผใใงๅฆ็ใใใใๆจๆบๆบๆ ใขใผใใงๅฆ็ใใใใๆฑบๅฎใใพใใใใผใธใง็ขบๅฎใซๅฎๅ จๆจๆบๆบๆ ใขใผใใไฝฟ็จใใใใใใซใใใซใฏใไปฅไธใฎไพใฎใใใช doctype ใไฝฟ็จใใใใใซใใฆใใ ใใใ
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<title>Hello World!</title>
</head>
<body></body>
</html>
ใใฎไพใซใใ doctype ใฎ <!doctype html> ใฏใใฃใจใใทใณใใซใชๅฝขๅผใงใใใHTML ๆจๆบใงๆจๅฅจใใใฆใใใใฎใฎใฒใจใคใงใใไปฅๅใฎใใผใธใงใณใฎ HTML ๆจๆบใงใฏไปใฎๅฝขๅผใๆจๅฅจใใฆใใพใใใใ็พ่กใฎใใฉใฆใถใผใฏใในใฆใใใฎ doctype ใซๅฏพใใฆ้ๅพๆนไบๆใขใผใใไฝฟ็จใใพใใใใ่ค้ใช doctype ใไฝฟ็จใในใ็็ฑใฏใใใพใใใไปใฎ doctype ใไฝฟ็จใใๅ ดๅใฏใๆบๆจๆบใขใผใใๅพๆนไบๆใขใผใใ้ฉ็จใใใใใใใใใใพใใ
doctype ใฏ HTML ๆๆธใฎๅ ้ ญใไปใฎใณใณใใณใใฎๅใซ็ฝฎใใใใซใใฆใใ ใใใ
<!doctype html> ใฎๅฏไธใฎ็ฎ็ใฏใ้ๅพๆนไบๆใขใผใใๆๅนใซใใใใจใ ใใงใใๅคใใใผใธใงใณใฎ HTML ๆจๆบใงใฏ doctype ใซไปใฎๆๅณใไธใใฆใใพใใใใใฌใณใใชใณใฐใขใผใใๅใๆฟใไปฅๅคใฎ็ฎ็ใง doctype ใไฝฟ็จใใใใฉใฆใถใผใฏใใใพใใใงใใใ
when different browsers choose various modes ใใ่ฆงใใ ใใใ
XHTML
ใใผใธใ XHTML ใจใใฆๆไพใใใใใซ application/xhtml+xml ใฎ MIME ใฟใคใใ Content-Type ใใใใผใงไฝฟ็จใใๅ ดๅใ doctype ใไฝฟ็จใใฆๆจๆบๆบๆ ใขใผใใๆๅนใซใใๅฟ
่ฆใฏใใใพใใใๆๆธใฏๅธธใซใๅฎๅ
จๆจๆบๆบๆ ใขใผใใใไฝฟ็จใใใใใใงใใ
text/html ใฎ MIME ใฟใคใใไฝฟ็จใใฆ XHTML ๅฝขๅผใฎใณใณใใณใใๆไพใใๅ ดๅใฏใใใฉใฆใถใผใ HTML ใจใใฆ่ชญใฟ่พผใฟใพใใฎใงใๆจๆบๆบๆ ใขใผใใไฝฟ็จใใใใใซ doctype ใๅฟ
่ฆใงใใ
ใฉใฎใขใผใใไฝฟใใใฆใใใใ็ขบ่ชใใใซใฏ
ใใผใธใๅพๆนไบๆใขใผใใพใใฏ้ๅฎๅพๆนไบๆใขใผใใงใฌใณใใชใณใฐใใใๅ ดๅใ Firefox ใฏ้็บ่ ใใผใซใฎใณใณใฝใผใซใฟใใซ่ญฆๅใใญใฐๅบๅใใพใใใใฎ่ญฆๅใ่กจ็คบใใใชใๅ ดๅใ Firefox ใฏ้ๅพๆนไบๆใขใผใใไฝฟ็จใใฆใใพใใ
JavaScript ใง document.compatMode ใฎๅคใๅๅพใใใจใใใฎๆๆธใไบๆใขใผใใงใใใใฉใใใ่กจ็คบใใใพใใ ใใฎๅคใ "BackCompat" ใฎๅ ดๅใใใฎๆๆธใฏๅพๆนไบๆใขใผใใงใใ ใใใงใชใๅ ดๅใฏใๅคใ "CSS1Compat" ใจใชใใพใใ