What is New in HTML5?
The DOCTYPE declaration for HTML5 is very simple:
<!DOCTYPE html>
The character encoding (charset) declaration is also very simple:
<meta charset="UTF-8">
HTML5 Example:
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Title of the document</title>
</head>
<body>
Content of the document......
</body>
</html>
<html>
<head>
<meta charset="UTF-8">
<title>Title of the document</title>
</head>
<body>
Content of the document......
</body>
</html>
 | The default character encoding in HTML5 is UTF-8. |
|---|
New HTML5 Elements
The most interesting new elements are:
New semantic elements like <header>, <footer>, <article>, and <section>.
New form control attributes like number, DATE
, time, calendar, and range.
, time, calendar, and range.
New graphic elements: <svg> and <canvas>.
New multimedia elements: <audio> and <video>.
| In the chapter HTML5 Support, you will learn how to "teach" old browsers to handle HTML5 semantic. |
|---|
New HTML5 API's (Application Programming Interfaces)
The most interesting new API's are:
- HTML Geolocation
- HTML Drag and Drop
- HTML Local Storage
- HTML Application Cache
- HTML Web Workers
- HTML SSE
| Local storage is a powerful replacement for cookies. |
|---|
Elements Removed in HTML5
The following HTML4 elements have been removed from HTML5:
| Element | Use instead |
|---|---|
| <acronym> | <abbr> |
| <applet> | <object> |
| <basefont> | CSS |
| <big> | CSS |
| <center> | CSS |
| <dir> | <ul> |
| <font> | CSS |
| <frame> | |
| <frameset> | |
| <noframes> | |
| <strike> | CSS |
| <tt> | CSS |
| In the chapter HTML5 Migration, you will learn how to easily migrate from HTML4 to HTML5. |
|---|
HTML History
Since the early days of the web, there have been many versions of HTML:
| Version | Year |
|---|---|
| Tim Berners-Lee invented www | 1989 |
| Tim Berners-Lee invented HTML | 1991 |
| Dave Raggett drafted HTML+ | 1993 |
| HTML Working Group defined HTML 2.0 | 1995 |
| W3C Recommended HTML 3.2 | 1997 |
| W3C Recommended HTML 4.01 | 1999 |
| W3C Recommended XHTML 1.0 | 2000 |
| HTML5 WHATWG First Public Draft | 2008 |
| HTML5 WHATWG Living Standard | 2012 |
| HTML5 W3C Final Recommendation | 2014 |
Tim Berners-Lee invented the "World Wide Web" in 1989, and the Internet took off in the 1990s.
From 1991 to 1998, HTML developed from version 1 to version 4.
In 2000, the World Wide Web Consortium (W3C) recommended XHTML 1.0.
The XHTML syntax was strict, and the developers were forced to write valid and "well-formed" code.
In 2004, WHATWG (Web Hypertext Application Technology Working Group) was formed in response to slow W3C development, and W3C's decision to close down the development of HTML, in favor of XHTML.
WHATWG wanted to develop HTML, consistent with how the web was used, while being backward compatible with older versions of HTML.
In the period 2004-2006, the WHATWG initiative gained support by the major browser vendors.
In 2006, W3C announced that they would support WHATWG.
In 2008, the first HTML5 public draft was released
In 2012, WHATWG and W3C decided on a separation:
WHATWG will develop HTML as a "Living Standard".
A living standard is never fully complete, but always updated and improved. New features can be added, but old functionality can not be removed.
The WHATWG Living Standard was published in 2012, and is continuously updated.
W3C will develop a definitive HTML5 and XHTML5 standard, as a "snapshot" of WHATWG.
The W3C HTML5 recommendation was released 28. October 2014.
HTML5 Browser Support
HTML5 is supported in all modern browsers.
In addition, all browsers, old and new, automatically handle unrecognized elements as inline elements.
Because of this, you can "teach" old browsers to handle "unknown" HTML elements.
| You can even teach stone age IE6 (Windows XP 2001) how to handle unknown HTML elements. |
|---|
Define HTML5 Elements as Block Elements
HTML5 defines 8 new semantic HTML elements. All these are block level elements.
To secure correct behavior in older browsers, you can set the CSS display property to block:
Example
header, section, footer, aside, nav, main, article, figure {
display: block;
}
display: block;
}
Adding New Elements to HTML
You can add any new element to HTML with a browser trick:
This example adds a new element called <myHero> to HTML, and defines a display style for it:
Example
<!DOCTYPE html>
<html>
<head>
<title>Creating an HTML Element</title>
<script>document.createElement("myHero")</script>
<style>
myHero {
display: block;
background-color: #ddd;
padding: 50px;
font-size: 30px;
}
</style>
</head>
<body>
<h1>My First Heading</h1>
<p>My first paragraph.</p>
<myHero>My First Hero</myHero>
</body>
</html>
<html>
<head>
<title>Creating an HTML Element</title>
<script>document.createElement("myHero")</script>
<style>
myHero {
display: block;
background-color: #ddd;
padding: 50px;
font-size: 30px;
}
</style>
</head>
<body>
<h1>My First Heading</h1>
<p>My first paragraph.</p>
<myHero>My First Hero</myHero>
</body>
</html>
Try it Yourself »
The JavaScript statement document.createElement("myHero") is added, only to satisfy IE.
Problem With Internet Explorer
You could use the solution described above, for all new HTML5 elements, but:
| Internet Explorer 8 and earlier, does not allow styling of unknown elements. |
|---|
Thankfully, Sjoerd Visscher created the "HTML5 Enabling JavaScript", "the shiv":
<!--[if lt IE 9]>
<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script>
<![endif]-->
<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script>
<![endif]-->
The code above is a comment, but versions previous to IE9 will read it (and understand it).
The Complete Shiv Solution
Example
<!DOCTYPE html>
<html>
<head>
<title>Styling HTML5</title>
<!--[if lt IE 9]>
<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script>
<![endif]-->
</head>
<body>
<h1>My First Article</h1>
<article>
London is the capital city of England. It is the most populous city in the United Kingdom, with a metropolitan area of over 13 million inhabitants.
</article>
</body>
</html>
<html>
<head>
<title>Styling HTML5</title>
<!--[if lt IE 9]>
<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script>
<![endif]-->
</head>
<body>
<h1>My First Article</h1>
<article>
London is the capital city of England. It is the most populous city in the United Kingdom, with a metropolitan area of over 13 million inhabitants.
</article>
</body>
</html>
Try it Yourself »
The link to the shiv code must be placed in the <head> element, because Internet Explorer needs to know about all new elements before reading them.
An HTML5 Skeleton
Example
<!DOCTYPE html>
<html lang="en">
<head>
<title>HTML5 Skeleton</title>
<meta charset="utf-8">
<!--[if lt IE 9]>
<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js">
</script>
<![endif]-->
<style>
body {font-family: Verdana, sans-serif; font-size:0.8em;}
header,nav, section,article,footer
{border:1px solid grey; margin:5px; padding:8px;}
nav ul {margin:0; padding:0;}
nav ul li {display:inline; margin:5px;}
</style>
</head>
<body>
<header>
<h1>HTML5 SKeleton</h1>
</header>
<nav>
<ul>
<li><a href="html5_semantic_elements.asp">HTML5 Semantic</a></li>
<li><a href="html5_geolocation.asp">HTML5 Geolocation</a></li>
<li><a href="html5_canvas.asp">HTML5 Graphics</a></li>
</ul>
</nav>
<section>
<h1>Famous Cities</h1>
<article>
<h2>London</h2>
<p>London is the capital city of England. It is the most populous city in the United Kingdom,
with a metropolitan area of over 13 million inhabitants.</p>
</article>
<article>
<h2>Paris</h2>
<p>Paris is the capital and most populous city of France.</p>
</article>
<article>
<h2>Tokyo</h2>
<p>Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
and the most populous metropolitan area in the world.</p>
</article>
</section>
<footer>
<p>© 2014 W3Schools. All rights reserved.</p>
</footer>
</body>
</html>
<html lang="en">
<head>
<title>HTML5 Skeleton</title>
<meta charset="utf-8">
<!--[if lt IE 9]>
<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js">
</script>
<![endif]-->
<style>
body {font-family: Verdana, sans-serif; font-size:0.8em;}
header,nav, section,article,footer
{border:1px solid grey; margin:5px; padding:8px;}
nav ul {margin:0; padding:0;}
nav ul li {display:inline; margin:5px;}
</style>
</head>
<body>
<header>
<h1>HTML5 SKeleton</h1>
</header>
<nav>
<ul>
<li><a href="html5_semantic_elements.asp">HTML5 Semantic</a></li>
<li><a href="html5_geolocation.asp">HTML5 Geolocation</a></li>
<li><a href="html5_canvas.asp">HTML5 Graphics</a></li>
</ul>
</nav>
<section>
<h1>Famous Cities</h1>
<article>
<h2>London</h2>
<p>London is the capital city of England. It is the most populous city in the United Kingdom,
with a metropolitan area of over 13 million inhabitants.</p>
</article>
<article>
<h2>Paris</h2>
<p>Paris is the capital and most populous city of France.</p>
</article>
<article>
<h2>Tokyo</h2>
<p>Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
and the most populous metropolitan area in the world.</p>
</article>
</section>
<footer>
<p>© 2014 W3Schools. All rights reserved.</p>
</footer>
</body>
</html>
Try it Yourself »
New Elements in HTML5
Below is a list of the new HTML5 elements, and a description of what they are used for.
New Semantic/Structural Elements
HTML5 offers new elements for better document structure:
| Tag | Description |
|---|---|
| <article> | Defines an article in the document |
| <aside> | Defines content aside from the page content |
| <bdi> | Defines a part of text that might be formatted in a different direction from other text |
| <details> | Defines additional details that the user can view or hide |
| <dialog> | Defines a dialog box or window |
| <figcaption> | Defines a caption for a <figure> element |
| <figure> | Defines self-contained content, like illustrations, diagrams, photos, code listings, etc. |
| <footer> | Defines a footer for the document or a section |
| <header> | Defines a header for the document or a section |
| <main> | Defines the main content of a document |
| <mark> | Defines marked or highlighted text |
| <menuitem> | Defines a command/menu item that the user can invoke from a popup menu |
| <meter> | Defines a scalar measurement within a known range (a gauge) |
| <nav> | Defines navigation links in the document |
| <progress> | Defines the progress of a task |
| <rp> | Defines what to show in browsers that do not support ruby annotations |
| <rt> | Defines an explanation/pronunciation of characters (for East Asian typography) |
| <ruby> | Defines a ruby annotation (for East Asian typography) |
| <section> | Defines a section in the document |
| <summary> | Defines a visible heading for a <details> element |
| <time> | Defines a DATE/time |
| <wbr> | Defines a possible line-break |
Read more about HTML5 Semantics.
New Form Elements
| Tag | Description |
|---|---|
| <datalist> | Defines pre-defined options for input controls |
| <keygen> | Defines a key-pair generator field (for forms) |
| <output> | Defines the result of a calculation |
Read all about old and new form elements in HTML Form Elements.
New Input Types
| New Input Types | New Input Attributes |
|---|---|
|
|
Learn all about old and new input types in HTML Input Types.
Learn all about input attributes in HTML Input Attributes.
HTML5 - New Attribute Syntax
HTML5 allows 4 different syntaxes for attributes.
This example demonstrates the different syntaxes used in an <input> tag:
| Type | Example |
|---|---|
| Empty | <input type="text" value="John Doe" disabled> |
| Unquoted | <input type="text" value=John> |
| Double-quoted | <input type="text" value="John Doe"> |
| Single-quoted | <input type="text" value='John Doe'> |
In HTML5, all 4 syntaxes may be used, depending on what is needed for the attribute.
HTML5 Graphics
| Tag | Description |
|---|---|
| <canvas> | Defines graphic drawing using JavaScript |
| <svg> | Defines graphic drawing using SVG |
Read more about HTML5 Canvas.
Read more about HTML5 SVG.
New Media Elements
| Tag | Description |
|---|---|
| <audio> | Defines sound or music content |
| <embed> | Defines containers for external applications (like plug-ins) |
| <source> | Defines sources for <video> and <audio> |
| <track> | Defines tracks for <video> and <audio> |
| <video> | Defines video or movie content |
Read more about HTML5 Video.
Read more about HTML5 Audio.
What are Semantic Elements?
A semantic element clearly describes its meaning to both the browser and the developer.
Examples of non-semantic elements: <div> and <span> - Tells nothing about its content.
Examples of semantic elements: <form>, <table>, and <img> - Clearly defines its content.
Browser Support
HTML5 semantic elements are supported in all modern browsers.
In addition, you can "teach" older browsers how to handle "unknown elements".
Read about it in HTML5 Browser Support.
New Semantic Elements in HTML5
Many web sites contain HTML code like: <div id="nav"> <div class="header"> <div id="footer">
to indicate navigation, header, and footer.
to indicate navigation, header, and footer.
HTML5 offers new semantic elements to define different parts of a web page:
- <article>
- <aside>
- <details>
- <figcaption>
- <figure>
- <footer>
- <header>
- <main>
- <mark>
- <nav>
- <section>
- <summary>
- <time>
HTML5 <section> Element
The <section> element defines a section in a document.
According to W3C's HTML5 documentation: "A section is a thematic grouping of content, typically with a heading."
A Web site's home page could be split into sections for introduction, content, and contact information.
Example
<section>
<h1>WWF</h1>
<p>The World Wide Fund for Nature (WWF) is....</p>
</section>
<h1>WWF</h1>
<p>The World Wide Fund for Nature (WWF) is....</p>
</section>
Try it Yourself »
HTML5 <article> Element
The <article> element specifies independent, self-contained content.
An article should make sense on its own, and it should be possible to read it independently from the rest of the web site.
Examples of where an <article> element can be used:
- Forum post
- Blog post
- Newspaper article
Example
<article>
<h1>What Does WWF Do?</h1>
<p>WWF's mission is to stop the degradation of our planet's natural environment,
and build a future in which humans live in harmony with nature.</p>
</article>
<h1>What Does WWF Do?</h1>
<p>WWF's mission is to stop the degradation of our planet's natural environment,
and build a future in which humans live in harmony with nature.</p>
</article>
Try it Yourself »
Nesting Semantic Elements
In the HTML5 standard, the <article> element defines a complete, self-contained block of related elements.
The <section> element is defined as a block of related elements.
Can we use the definitions to decide how to nest elements? No, we cannot!
On the Internet, you will find HTML pages with <section> elements containing <article> elements, and <article> elements containing <sections> elements.
You will also find pages with <section> elements containing <section> elements, and <article> elements containing <article> elements.
| Newspaper: The sports articles in the sports section, have a technical section in each article. |
|---|
HTML5 <header> Element
The <header> element specifies a header for a document or section.
The <header> element should be used as a container for introductory content.
You can have several <header> elements in one document.
The following example defines a header for an article:
Example
<article>
<header>
<h1>What Does WWF Do?</h1>
<p>WWF's mission:</p>
</header>
<p>WWF's mission is to stop the degradation of our planet's natural environment,
and build a future in which humans live in harmony with nature.</p>
</article>
<header>
<h1>What Does WWF Do?</h1>
<p>WWF's mission:</p>
</header>
<p>WWF's mission is to stop the degradation of our planet's natural environment,
and build a future in which humans live in harmony with nature.</p>
</article>
Try it Yourself »
HTML5 <footer> Element
The <footer> element specifies a footer for a document or section.
A <footer> element should contain information about its containing element.
A footer typically contains the author of the document, copyright information, links to terms of use, contact information, etc.
You can have several <footer> elements in one document.
Example
<footer>
<p>Posted by: Hege Refsnes</p>
<p>Contact information: <a href="mailto:someone@example.com">
someone@example.com</a>.</p>
</footer>
<p>Posted by: Hege Refsnes</p>
<p>Contact information: <a href="mailto:someone@example.com">
someone@example.com</a>.</p>
</footer>
Try it Yourself »
HTML5 <nav> Element
The <nav> element defines a set of navigation links.
The <nav> element is intended for large blocks of navigation links. However, not all links in a document should be inside a <nav> element!
Example
<nav>
<a href="/html/">HTML</a> |
<a href="/css/">CSS</a> |
<a href="/js/">JavaScript</a> |
<a href="/jquery/">jQuery</a>
</nav>
<a href="/html/">HTML</a> |
<a href="/css/">CSS</a> |
<a href="/js/">JavaScript</a> |
<a href="/jquery/">jQuery</a>
</nav>
Try it Yourself »
HTML5 <aside> Element
The <aside> element defines some content aside from the content it is placed in (like a sidebar).
The aside content should be related to the surrounding content.
Example
<p>My family and I visited The Epcot center this summer.</p>
<aside>
<h4>Epcot Center</h4>
<p>The Epcot Center is a theme park in Disney World, Florida.</p>
</aside>
<aside>
<h4>Epcot Center</h4>
<p>The Epcot Center is a theme park in Disney World, Florida.</p>
</aside>
Try it Yourself »
HTML5 <figure> and <figcaption> Elements
In books and newspapers, it is common to have captions with images.
The purpose of a caption is to add a visual explanation to an image.
With HTML5, images and captions can be grouped together in <figure> elements:
Example
<figure>
<img src="pic_mountain.jpg" alt="The Pulpit Rock" width="304" height="228">
<figcaption>Fig1. - The Pulpit Rock, Norway.</figcaption>
</figure>
<img src="pic_mountain.jpg" alt="The Pulpit Rock" width="304" height="228">
<figcaption>Fig1. - The Pulpit Rock, Norway.</figcaption>
</figure>
Try it Yourself »
The <img> element defines the image, the <figcaption> element defines the caption.
Why Semantic HTML5 Elements?
With HTML4, developers used their own favorite attribute names to style page elements:
header, top, bottom, footer, menu, navigation, main, container, content, article, sidebar, topnav, ...
This made it impossible for search engines to identify the correct web page content.
With HTML5 elements like: <header> <footer> <nav> <section> <article>, this will become easier.
According to the W3C, a Semantic Web:
"Allows data to be shared and reused across applications, enterprises, and communities."
Migration from HTML4 to HTML5
This chapter is entirely about how to migrate from a typical HTML4 page to a typical HTML5 page.
This chapter demonstrates how to convert an existing HTML4 page into an HTML5 page, without destroying anything of the original content or structure.
| You can migrate to HTML5 from HTML4, and XHTML, using the same recipe. |
|---|
| Typical HTML4 | Typical HTML5 |
|---|---|
| <div id="header"> | <header> |
| <div id="menu"> | <nav> |
| <div id="content"> | <section> |
| <div id="post"> | <article> |
| <div id="footer"> | <footer> |
A Typical HTML4 Page
Example
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html;charset=utf-8">
<title>HTML4</title>
<style>
body {font-family:Verdana,sans-serif;font-size:0.8em;}
div#header,div#footer,div#content,div#post
{border:1px solid grey;margin:5px;margin-bottom:15px;padding:8px;background-color:white;}
div#header,div#footer {color:white;background-color:#444;margin-bottom:5px;}
div#content {background-color:#ddd;}
div#menu ul {margin:0;padding:0;}
div#menu ul li {display:inline; margin:5px;}
</style>
</head>
<body>
<div id="header">
<h1>Monday Times</h1>
</div>
<div id="menu">
<ul>
<li>News</li>
<li>Sports</li>
<li>Weather</li>
</ul>
</div>
<div id="content">
<h2>News Section</h2>
<div id="post">
<h2>News Article</h2>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
</div>
<div id="post">
<h2>News Article</h2>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
</div>
</div>
<div id="footer">
<p>&copy; 2014 Monday Times. All rights reserved.</p>
</div>
</body>
</html>
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html;charset=utf-8">
<title>HTML4</title>
<style>
body {font-family:Verdana,sans-serif;font-size:0.8em;}
div#header,div#footer,div#content,div#post
{border:1px solid grey;margin:5px;margin-bottom:15px;padding:8px;background-color:white;}
div#header,div#footer {color:white;background-color:#444;margin-bottom:5px;}
div#content {background-color:#ddd;}
div#menu ul {margin:0;padding:0;}
div#menu ul li {display:inline; margin:5px;}
</style>
</head>
<body>
<div id="header">
<h1>Monday Times</h1>
</div>
<div id="menu">
<ul>
<li>News</li>
<li>Sports</li>
<li>Weather</li>
</ul>
</div>
<div id="content">
<h2>News Section</h2>
<div id="post">
<h2>News Article</h2>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
</div>
<div id="post">
<h2>News Article</h2>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
</div>
</div>
<div id="footer">
<p>&copy; 2014 Monday Times. All rights reserved.</p>
</div>
</body>
</html>
Try it Yourself »
Change to HTML5 Doctype
Change the doctype, from the HTML4 doctype:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
to the HTML5 doctype:
Change to HTML5 Encoding
Change the encoding information, from HTML4:
<meta http-equiv="Content-Type" content="text/html;charset=utf-8">
to HTML5:
Add The Shiv
HTML5 semantic elements are supported in all modern browsers.
In addition, you can "teach" older browsers how to handle "unknown elements".
Add the shiv for Internet Explorer support:
<!--[if lt IE 9]>
<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script>
<![endif]-->
<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script>
<![endif]-->
Try it Yourself »
| Read about the shiv in HTML5 Browser Support. |
|---|
Add CSS for HTML5 Semantic Elements
Look at your existing CSS styles:
div#header,div#footer,div#content,div#post {
border:1px solid grey;margin:5px;margin-bottom:15px;padding:8px;background-color:white;
}
div#header,div#footer {
color:white;background-color:#444;margin-bottom:5px;
}
div#content {
background-color:#ddd;
}
div#menu ul {
margin:0;padding:0;
}
div#menu ul li {
display:inline; margin:5px;
}
border:1px solid grey;margin:5px;margin-bottom:15px;padding:8px;background-color:white;
}
div#header,div#footer {
color:white;background-color:#444;margin-bottom:5px;
}
div#content {
background-color:#ddd;
}
div#menu ul {
margin:0;padding:0;
}
div#menu ul li {
display:inline; margin:5px;
}
Duplicate with equal CSS styles for HTML5 semantic elements:
header,footer,section,article {
border:1px solid grey;margin:5px;margin-bottom:15px;padding:8px;background-color:white;
}
header,footer {
color:white;background-color:#444;margin-bottom:5px;
}
section {
background-color:#ddd;
}
nav ul {
margin:0;padding:0;
}
nav ul li {
display:inline; margin:5px;
}
border:1px solid grey;margin:5px;margin-bottom:15px;padding:8px;background-color:white;
}
header,footer {
color:white;background-color:#444;margin-bottom:5px;
}
section {
background-color:#ddd;
}
nav ul {
margin:0;padding:0;
}
nav ul li {
display:inline; margin:5px;
}
Try it Yourself »
Change to HTML5 <header> and <footer>
Change the <div> elements with id="header" and id="footer":
<div id="header">
<h1>Monday Times</h1>
</div>
.
.
.
<div id="footer">
<p>&copy; 2014 W3Schools. All rights reserved.</p>
</div>
<h1>Monday Times</h1>
</div>
.
.
.
<div id="footer">
<p>&copy; 2014 W3Schools. All rights reserved.</p>
</div>
to HTML5 semantic <header> and <footer> elements:
<header>
<h1>Monday Times</h1>
</header>
.
.
.
<footer>
<p>© 2014 W3Schools. All rights reserved.</p>
</footer>
<h1>Monday Times</h1>
</header>
.
.
.
<footer>
<p>© 2014 W3Schools. All rights reserved.</p>
</footer>
Try it Yourself »
Change to HTML5 <nav>
Change the <div> element with id="menu":
<div id="menu">
<ul>
<li>News</li>
<li>Sports</li>
<li>Weather</li>
</ul>
</div>
<ul>
<li>News</li>
<li>Sports</li>
<li>Weather</li>
</ul>
</div>
to an HTML5 semantic <nav> element:
Change to HTML5 <section>
Change the <div> element with id="content":
<div id="content">
.
.
.
</div>
.
.
.
</div>
to an HTML5 semantic <section> element:
Change to HTML5 <article>
Change all <div> element with class="post":
<div class="post">
<h2>News Article</h2>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
</div>
<h2>News Article</h2>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
</div>
to HTML5 semantic <article> elements:
<article>
<h2>News Article</h2>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
</article>
<h2>News Article</h2>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
</article>
Try it Yourself »
Remove these "no longer needed" <style> elements:
div#header,div#footer,div#content,div#post {
border:1px solid grey;margin:5px;margin-bottom:15px;padding:8px;background-color:white;
}
div#header,div#footer {
color:white;background-color:#444;margin-bottom:5px;
}
div#content {
background-color:#ddd;
}
div#menu ul {
margin:0;padding:0;
}
div#menu ul li {
display:inline; margin:5px;
}
border:1px solid grey;margin:5px;margin-bottom:15px;padding:8px;background-color:white;
}
div#header,div#footer {
color:white;background-color:#444;margin-bottom:5px;
}
div#content {
background-color:#ddd;
}
div#menu ul {
margin:0;padding:0;
}
div#menu ul li {
display:inline; margin:5px;
}
Try it Yourself »
A Typical HTML5 Page
Finally you can remove the <head> tags. They are not needed in HTML5:
Example
<!DOCTYPE html>
<html lang="en">
<title>HTML5</title>
<meta charset="utf-8">
<!--[if lt IE 9]>
<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js">
</script>
<![endif]-->
<style>
body {
font-family:Verdana,sans-serif;font-size:0.8em;
}
header,footer,section,article {
border:1px solid grey;
margin:5px;margin-bottom:15px;padding:8px;
background-color:white;
}
header,footer {
color:white;background-color:#444;margin-bottom:5px;
}
section {
background-color:#ddd;
}
nav ul {
margin:0;padding:0;
}
nav ul li {
display:inline; margin:5px;
}
</style>
<body>
<header>
<h1>Monday Times</h1>
</header>
<nav>
<ul>
<li>News</li>
<li>Sports</li>
<li>Weather</li>
</ul>
</nav>
<section>
<h2>News Section</h2>
<article>
<h2>News Article</h2>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
</article>
<article>
<h2>News Article</h2>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
</article>
</section>
<footer>
<p>&copy; 2014 Monday Times. All rights reserved.</p>
</footer>
</body>
</html>
<html lang="en">
<title>HTML5</title>
<meta charset="utf-8">
<!--[if lt IE 9]>
<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js">
</script>
<![endif]-->
<style>
body {
font-family:Verdana,sans-serif;font-size:0.8em;
}
header,footer,section,article {
border:1px solid grey;
margin:5px;margin-bottom:15px;padding:8px;
background-color:white;
}
header,footer {
color:white;background-color:#444;margin-bottom:5px;
}
section {
background-color:#ddd;
}
nav ul {
margin:0;padding:0;
}
nav ul li {
display:inline; margin:5px;
}
</style>
<body>
<header>
<h1>Monday Times</h1>
</header>
<nav>
<ul>
<li>News</li>
<li>Sports</li>
<li>Weather</li>
</ul>
</nav>
<section>
<h2>News Section</h2>
<article>
<h2>News Article</h2>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
</article>
<article>
<h2>News Article</h2>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum
lurum hurum turum.</p>
</article>
</section>
<footer>
<p>&copy; 2014 Monday Times. All rights reserved.</p>
</footer>
</body>
</html>
Try it Yourself »
The Difference Between <article> <section> and <div>
There is a confusing (lack of) difference in the HTML5 standard, between <article> <section> and <div>.
In the HTML5 standard, the <section> element is defined as a block of related elements.
The <article> element is defined as a complete, self-contained block of related elements.
The <div> element is defined as a block of children elements.
How to interpret that?
In the example above, we have used <section> as a container for related <articles>.
But, we could have used <article> as a container for articles as well.
Here are some different examples:
<article> in <article>:
<article>
<h2>Famous Cities</h2>
<article>
<h2>London</h2>
<p>London is the capital city of England. It is the most populous city in the United Kingdom,
with a metropolitan area of over 13 million inhabitants.</p>
</article>
<article>
<h2>Paris</h2>
<p>Paris is the capital and most populous city of France.</p>
</article>
<article>
<h2>Tokyo</h2>
<p>Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
and the most populous metropolitan area in the world.</p>
</article>
</article>
<h2>Famous Cities</h2>
<article>
<h2>London</h2>
<p>London is the capital city of England. It is the most populous city in the United Kingdom,
with a metropolitan area of over 13 million inhabitants.</p>
</article>
<article>
<h2>Paris</h2>
<p>Paris is the capital and most populous city of France.</p>
</article>
<article>
<h2>Tokyo</h2>
<p>Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
and the most populous metropolitan area in the world.</p>
</article>
</article>
Try it Yourself »
<div> in <article>:
<article>
<h2>Famous Cities</h2>
<div class="city">
<h2>London</h2>
<p>London is the capital city of England. It is the most populous city in the United Kingdom,
with a metropolitan area of over 13 million inhabitants.</p>
</div>
<div class="city">
<h2>Paris</h2>
<p>Paris is the capital and most populous city of France.</p>
</div>
<div class="city">
<h2>Tokyo</h2>
<p>Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
and the most populous metropolitan area in the world.</p>
</div>
</article>
<h2>Famous Cities</h2>
<div class="city">
<h2>London</h2>
<p>London is the capital city of England. It is the most populous city in the United Kingdom,
with a metropolitan area of over 13 million inhabitants.</p>
</div>
<div class="city">
<h2>Paris</h2>
<p>Paris is the capital and most populous city of France.</p>
</div>
<div class="city">
<h2>Tokyo</h2>
<p>Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
and the most populous metropolitan area in the world.</p>
</div>
</article>
Try it Yourself »
<div> in <section> in <article>:
<article>
<section>
<h2>Famous Cities</h2>
<div class="city">
<h2>London</h2>
<p>London is the capital city of England. It is the most populous city in the United Kingdom,
with a metropolitan area of over 13 million inhabitants.</p>
</div>
<div class="city">
<h2>Paris</h2>
<p>Paris is the capital and most populous city of France.</p>
</div>
<div class="city">
<h2>Tokyo</h2>
<p>Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
and the most populous metropolitan area in the world.</p>
</div>
</section>
<section>
<h2>Famous Countries</h2>
<div class="country">
<h2>England</h2>
<p>London is the capital city of England. It is the most populous city in the United Kingdom,
with a metropolitan area of over 13 million inhabitants.</p>
</div>
<div class="country">
<h2>France</h2>
<p>Paris is the capital and most populous city of France.</p>
</div>
<div class="country">
<h2>Japan</h2>
<p>Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
and the most populous metropolitan area in the world.</p>
</div>
</section>
</article>
<section>
<h2>Famous Cities</h2>
<div class="city">
<h2>London</h2>
<p>London is the capital city of England. It is the most populous city in the United Kingdom,
with a metropolitan area of over 13 million inhabitants.</p>
</div>
<div class="city">
<h2>Paris</h2>
<p>Paris is the capital and most populous city of France.</p>
</div>
<div class="city">
<h2>Tokyo</h2>
<p>Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
and the most populous metropolitan area in the world.</p>
</div>
</section>
<section>
<h2>Famous Countries</h2>
<div class="country">
<h2>England</h2>
<p>London is the capital city of England. It is the most populous city in the United Kingdom,
with a metropolitan area of over 13 million inhabitants.</p>
</div>
<div class="country">
<h2>France</h2>
<p>Paris is the capital and most populous city of France.</p>
</div>
<div class="country">
<h2>Japan</h2>
<p>Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
and the most populous metropolitan area in the world.</p>
</div>
</section>
</article>
Try it Yourself »
HTML Coding Conventions
Web developers are often uncertain about the coding style and syntax to use in HTML.
Between 2000 and 2010, many web developers converted from HTML to XHTML.
With XHTML, developers were forced to write valid and "well-formed" code.
HTML5 is a bit more sloppy when it comes to code validation.
With HTML5, you must create your own Best Practice, Style Guide and Coding Conventions.
Be Smart and Future Proof
A consequent use of style, makes it easier for others to understand and use your HTML.
In the future, programs like XML readers, may want to read your HTML.
Using a well-formed "close to XHTML" syntax, can be smart.
| Always keep your style smart, tidy, clean, and well-formed. |
|---|
Use Correct Document Type
Always declare the document type as the first line in your document:
<!DOCTYPE html>
If you want consistently with lower case tags, you can use:
<!doctype html>
Use Lower Case Element Names
HTML5 allows mixing uppercase and lowercase letters in element names.
We recommend using lowercase element names:
- Mixing uppercase and lowercase names is bad
- Developers are used to use lowercase names (as in XHTML)
- Lowercase look cleaner
- Lowercase are easier to write
Bad:
<SECTION>
<p>This is a paragraph.</p>
</SECTION>
<p>This is a paragraph.</p>
</SECTION>
Very Bad:
<Section>
<p>This is a paragraph.</p>
</SECTION>
<p>This is a paragraph.</p>
</SECTION>
Good:
<section>
<p>This is a paragraph.</p>
</section>
<p>This is a paragraph.</p>
</section>
Close All HTML Elements
In HTML5, you don't have to close all elements (for example the <p> element).
We recommend closing all HTML elements:
Looking bad:
<section>
<p>This is a paragraph.
<p>This is a paragraph.
</section>
<p>This is a paragraph.
<p>This is a paragraph.
</section>
Looking good:
<section>
<p>This is a paragraph.</p>
<p>This is a paragraph.</p>
</section>
<p>This is a paragraph.</p>
<p>This is a paragraph.</p>
</section>
Close Empty HTML Elements
In HTML5, it is optional to close empty elements.
This is allowed:
<meta charset="utf-8">
This is also allowed:
<meta charset="utf-8" />
The slash (/) is required in XHTML and XML.
If you expect XML software to access your page, it might be a good idea to keep it.
Use Lower Case Attribute Names
HTML5 allows mixing uppercase and lowercase letters in attribute names.
We recommend using lowercase attribute names:
- Mixing uppercase and lowercase names is bad
- Developers are used to use lowercase names (as in XHTML)
- Lowercase look cleaner
- Lowercase are easier to write
Looking bad:
<div CLASS="menu">
Looking good:
<div class="menu">
Quote Attribute Values
HTML5 allows attribute values without quotes.
We recommend quoting attribute values:
- You have to use quotes if the value contains spaces
- Mixing styles is never good
- Quoted values are easier to read
This will not work, because the value contains spaces:
<table class=table striped>
This will work:
<table class="table striped">
Image Attributes
Always use the alt attribute with images. It is important when the image cannot be viewed.
<img src="html5.gif" alt="HTML5" style="width:128px;height:128px">
Always define image size. It reduces flickering because the browser can reserve space for images before they are loaded.
<img src="html5.gif" alt="HTML5" style="width:128px;height:128px">
Spaces and Equal Signs
Spaces around equal signs is legal:
<link rel = "stylesheet" href = "styles.css">
But space-less is easier to read, and groups entities better together:
<link rel="stylesheet" href="styles.css">
Avoid Long Code Lines
When using an HTML editor, it is inconvenient to scroll right and left to read the HTML code.
Try to avoid code lines longer than 80 characters.
Blank Lines and Indentation
Do not add blank lines without a reason.
For readability, add blank lines to separate large or logical code blocks.
For readability, add 2 spaces of indentation. Do not use TAB.
Do not use unnecessary blank lines and indentation. It is not necessary to use blank lines between short and related items. It is not necessary to indent every element:
Unnecessary:
<body>
<h1>Famous Cities</h1>
<h2>Tokyo</h2>
<p>
Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
and the most populous metropolitan area in the world.
It is the seat of the Japanese government and the Imperial Palace,
and the home of the Japanese Imperial Family.
</p>
</body>
<h1>Famous Cities</h1>
<h2>Tokyo</h2>
<p>
Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
and the most populous metropolitan area in the world.
It is the seat of the Japanese government and the Imperial Palace,
and the home of the Japanese Imperial Family.
</p>
</body>
Better:
<body>
<h1>Famous Cities</h1>
<h2>Tokyo</h2>
<p>
Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
and the most populous metropolitan area in the world.
It is the seat of the Japanese government and the Imperial Palace,
and the home of the Japanese Imperial Family.
</p>
</body>
<h1>Famous Cities</h1>
<h2>Tokyo</h2>
<p>
Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
and the most populous metropolitan area in the world.
It is the seat of the Japanese government and the Imperial Palace,
and the home of the Japanese Imperial Family.
</p>
</body>
Table Example:
<table>
<tr>
<th>Name</th>
<th>Description</th>
</tr>
<tr>
<td>A</td>
<td>Description of A</td>
</tr>
<tr>
<td>B</td>
<td>Description of B</td>
</tr>
</table>
<tr>
<th>Name</th>
<th>Description</th>
</tr>
<tr>
<td>A</td>
<td>Description of A</td>
</tr>
<tr>
<td>B</td>
<td>Description of B</td>
</tr>
</table>
List Example:
<ol>
<li>LondonA</li>
<li>Paris</li>
<li>Tokyo</li>
</ol>
<li>LondonA</li>
<li>Paris</li>
<li>Tokyo</li>
</ol>
Omitting <html> and <body>?
In the HTML5 standard, the <html> tag and the <body> tag can be omitted.
The following code will validate as HTML5:
Example
<!DOCTYPE html>
<head>
<title>Page Title</title>
</head>
<h1>This is a heading</h1>
<p>This is a paragraph.</p>
<head>
<title>Page Title</title>
</head>
<h1>This is a heading</h1>
<p>This is a paragraph.</p>
Try it Yourself »
We do not recommend omitting the <html> and <body> tags.
The <html> element is the document root. It is the recommended place for specifying the page language:
<!DOCTYPE html>
<html lang="en-US">
<html lang="en-US">
Declaring a language is important for accessibility applications (screen readers) and search engines.
Omitting <html> or <body> can crash DOM and XML software.
Omitting <body> can produce errors in older browsers (IE9).
Omitting <head>?
In the HTML5 standard, the <head> tag can also be omitted.
By default, browsers will add all elements before <body>, to a default <head> element.
You can reduce the complexity of HTML, by omitting the <head> tag:
Example
<!DOCTYPE html>
<html>
<title>Page Title</title>
<body>
<h1>This is a heading</h1>
<p>This is a paragraph.</p>
</body>
</html>
<html>
<title>Page Title</title>
<body>
<h1>This is a heading</h1>
<p>This is a paragraph.</p>
</body>
</html>
Try it Yourself »
| Omitting tags is unfamiliar to web developers. It needs time to be established as a guideline. |
|---|
Meta Data
The <title> element is required in HTML5. Make the title as meaningful as possible:
<title>HTML5 Syntax and Coding Style</title>
To ensure proper interpretation, and correct search engine indexing, both the language and the character encoding should be defined as early as possible in a document:
<!DOCTYPE html>
<html lang="en-US">
<head>
<meta charset="UTF-8">
<title>HTML5 Syntax and Coding Style</title>
</head>
<html lang="en-US">
<head>
<meta charset="UTF-8">
<title>HTML5 Syntax and Coding Style</title>
</head>
HTML Comments
Short comments should be written on one line, with a space after <!-- and a space before -->:
<!-- This is a comment -->
Long comments, spanning many lines, should be written with <!-- and --> on separate lines:
<!--
This is a long comment example. This is a long comment example. This is a long comment example.
This is a long comment example. This is a long comment example. This is a long comment example.
-->
This is a long comment example. This is a long comment example. This is a long comment example.
This is a long comment example. This is a long comment example. This is a long comment example.
-->
Long comments are easier to observe, if they are indented 2 spaces.
Style Sheets
Use simple syntax for linking style sheets (the type attribute is not necessary):
<link rel="stylesheet" href="styles.css">
Short rules can be written compressed, on one line, like this:
p.into {font-family:"Verdana"; font-size:16em;}
Long rules should be written over multiple lines:
body {
background-color: lightgrey;
font-family: "Arial Black", Helvetica, sans-serif;
font-size: 16em;
color: black;
}
background-color: lightgrey;
font-family: "Arial Black", Helvetica, sans-serif;
font-size: 16em;
color: black;
}
- Place the opening bracket on the same line as the selector.
- Use one space before the opening bracket.
- Use 2 spaces of indentation.
- Use colon plus one space between each property and its value.
- Use space after each comma or semicolon.
- Use semicolon after each property-value pair, including the last.
- Only use quotes around values if the value contains spaces.
- Place the closing bracket on a new line, without leading spaces.
- Avoid lines over 80 characters.
| Adding a space after a comma, or a semicolon, is a general rule in all types of writing. |
|---|
Loading JavaScript in HTML
Use simple syntax for loading external scripts (the type attribute is not necessary):
<script src="myscript.js">
Accessing HTML Elements with JavaScript
A consequence of using "untidy" HTML styles, might result in JavaScript errors.
These two JavaScript statements will produce different results:
If possible, use the same naming convention (as JavaScript) in HTML.
Use Lower Case File Names
Most web servers (Apache, Unix) are case sensitive about file names:
london.jpg cannot be accessed as London.jpg.
Other web servers (Microsoft, IIS) are not case sensitive:
london.jpg can be accessed as London.jpg or london.jpg.
If you use a mix of upper and lower case, you have to be extremely consistent.
If you move from a case insensitive, to a case sensitive server, even small errors will break your web.
To avoid these problems, always use lower case file names (if possible).
File Extensions
HTML files should have a .html extension (not .htm).
CSS files should have a .css extension.
JavaScript files should have a .js extension.
Semantic Elements in HTML5
Below is an alphabetical list of the new semantic elements in HTML5.
The links goes to our complete HTML5 Reference.
| Tag | Description |
|---|---|
| <article> | Defines an article |
| <aside> | Defines content aside from the page content |
| <details> | Defines additional details that the user can view or hide |
| <figcaption> | Defines a caption for a <figure> element |
| <figure> | Specifies self-contained content, like illustrations, diagrams, photos, code listings, etc. |
| <footer> | Defines a footer for a document or section |
| <header> | Specifies a header for a document or section |
| <main> | Specifies the main content of a document |
| <mark> | Defines marked/highlighted text |
| <nav> | Defines navigation links |
| <section> | Defines a section in a document |
| <summary> | Defines a visible heading for a <details> element |
| <time> | Defines a DATE/time |
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