Post on 19-Jan-2020
Introduction to
HTML5
History of HTML
HTML first published1991
2012
2002 -
2009
2000
HTML 2.0
HTML 3.2
HTML 4.01
XHTML 1.0
XHTML 2.0
HTML5
1995
1997
1999
HTML5 is much more tolerant and can
handle markup from all the prior versions.
Though HTML5 was published officially in 2012, it
has been in development since 2004.
After HTML 4.01 was released, focus
shifted to XHTML and its stricter standards.
XHTML 2.0 By combining the strengths of
HTML and XML, XHTML was developed.
XHTML is HTML redesigned as XML.
What is HTML5?
� HTML5 is the newest version of HTML, only recently
gaining partial support by the makers of web browsers.
� It incorporates all features from earlier versions of HTML,
including the stricter XHTML.
� It adds a diverse set of new tools for the web developer
to use.
� It is still a work in progress. No browsers have full
HTML5 support. It will be many years – perhaps not
until 2018 or later - before being fully defined and
supported.
Goals of HTML5
� Support all existing web pages. With HTML5, there is no
requirement to go back and revise older websites.
� Reduce the need for external plugins and scripts to show
website content.
� Improve the semantic definition (i.e. meaning and
purpose) of page elements.
� Make the rendering of web content universal and
independent of the device being used.
� Handle web documents errors in a better and more
consistent fashion.
New Elements in HTML5
<figcaption>
<footer>
<header>
<hgroup>
<mark>
<nav>
<progress>
<section>
<source>
<svg>
<time>
<video>
These are just some of the new elements introduced in HTML5. We
will be exploring each of these during this course.
<article>
<aside>
<audio>
<canvas>
<datalist>
<figure>
Other New Features in HTML5
� Built-in audio and video support (without plugins)
� Enhanced form controls and attributes
� The Canvas (a way to draw directly on a web page)
� Drag and Drop functionality
� Support for CSS3 (the newer and more powerful version
of CSS)
� More advanced features for web developers, such as
data storage and offline applications.
First Look at HTML5
Remember the DOCTYPE declaration from XHTML?
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
In HTML5, there is just one possible DOCTYPE declaration and it is simpler:
<!DOCTYPE html>
Just 15 characters!
The DOCTYPE tells the browser which type and version of document to
expect. This should be the last time the DOCTYPE is ever changed. From
now on, all future versions of HTML will use this same simplified declaration.
The <html> Element
This is what the <html> element looked like in XHTML:
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en"
lang="en">
Again, HTML5 simplifies this line:
<html lang="en">
Each of the world’s major languages has a two-character code, e.g. Spanish = "es",
French = "fr", German = "de", Chinese = "zh", Arabic = "ar".
The lang attribute in the <html> element declares which language the page
content is in. Though not strictly required, it should always be specified, as it
can assist search engines and screen readers.
The <head> Section
Here is a typical XHTML <head> section:
<head>
<meta http-equiv="Content-type" content="text/html; charset=UTF-8" />
<title>My First XHTML Page</title>
<link rel="stylesheet" type="text/css" href="style.css" />
</head>
And the HTML5 version:
Notice the simplified character set declaration, the shorter CSS stylesheet link
text, and the removal of the trailing slashes for these two lines.
<head>
<meta charset="utf-8">
<title>My First HTML5 Page</title>
<link rel="stylesheet" href="style.css">
</head>
Basic HTML5 Web Page
Putting the prior sections together, and now adding the <body> section and
closing tags, we have our first complete web page in HTML5:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>My First HTML5 Page</title>
<link rel="stylesheet" href="style.css">
</head>
<body>
<p>HTML5 is fun!</p>
</body>
</html>
Let's open this page in a web browser to see how it looks…
Viewing the HTML5 Web Page
Even though we used HTML5, the page looks exactly the same in a web
browser as it would in XHTML. Without looking at the source code, web
visitors will not know which version of HTML the page was created with.
HTML 5
� Latest revision of HTML
� Backward compatible
� New key features:
�video and audio tags
�content-specific tags
� tags for form elements
�canvas element
�storage of user data© 2016 Pearson Education,
Inc., Hoboken, NJ. All rights
reserved. 12
Video and Audio Tags
� Allow simple code for adding video and audio on Web pages
� Video and audio are played back by the Web browser's built-in player, not plug-ins
© 2016 Pearson Education,
Inc., Hoboken, NJ. All rights
reserved. 13
Content-Specific Tags
� Examples: <footer>, <header>, <nav>, <article>, <section>, <figure>, <summary>, <aside>
� Allow mark up content by semantics
� Provide a standardized system to classify the information on Web pages
© 2016 Pearson Education,
Inc., Hoboken, NJ. All rights
reserved. 14
Form Elements
� Examples: date picker, color picker, numeric stepper, new input types (email, url, and search)
� To enhance user experience of filling out forms
© 2016 Pearson Education,
Inc., Hoboken, NJ. All rights
reserved. 15
Canvas
� Allows drawing graphics and placing images dynamically inside it using JavaScript
� Visual content inside it can be scripted to change over time (hence animation) and in response to the user interaction (mouse clicks and key presses)
� Used for animation and game development
© 2016 Pearson Education,
Inc., Hoboken, NJ. All rights
reserved. 16
Storage of User Data
� Approx. 5 MB depending on browsers
� Larger data limit than cookies (4 KB limit)
� Storage and retrieval of data on the user's device; i.e., no need for databases or user accounts set up on the server
© 2016 Pearson Education,
Inc., Hoboken, NJ. All rights
reserved. 17
XHTML vs. HTML 5
� DOCTYPE declaration
� Character encoding
� Cases for tag and attribute names
� Values of attributes
� Boolean attribute
� End tag
© 2016 Pearson Education,
Inc., Hoboken, NJ. All rights
reserved. 18
DOCTYPE Declaration
XHTML HTML 5
Three doctypes: Strict, Transitional, and Frameset
For example:<!DOCTYPE html PUBLIC "-
//W3C//DTD XHTML 1.0
Transitional//EN" "
http://www.w3.org/TR/xhtm
l1/DTD/xhtml1-
transitional.dtd ">
Only one simplified doctypedeclared likethis:<!DOCTYPE HTML>
© 2016 Pearson Education,
Inc., Hoboken, NJ. All rights
reserved. 19
Character Encoding
XHTML HTML 5
<meta http-
equiv="Content-
Type"
content="text/html;
charset=utf-8" />
Simplified as follows:<meta charset"UTF-
8"/>
© 2016 Pearson Education,
Inc., Hoboken, NJ. All rights
reserved. 20
Cases for Tag and Attribute
NamesXHTML HTML 5
All lowercase No restriction
© 2016 Pearson Education,
Inc., Hoboken, NJ. All rights
reserved. 21
Value of an Attribute
XHTML HTML 5
Enclosed in quotation marks Does not have to be in
quotation marks
© 2016 Pearson Education,
Inc., Hoboken, NJ. All rights
reserved. 22
Boolean Attribute
XHTML HTML 5
The value "true" or "false" has to
be written out and enclosed in
quotation mark; for example:
<div hidden="true" />
No need to write out the value—
just the
presence of the attribute means it
is true;
for example:
<div hidden />
© 2016 Pearson Education,
Inc., Hoboken, NJ. All rights
reserved. 23
End Tag
XHTML HTML 5
Required for each start tag Not required; thus, self-closing
is not required for those tags
without content, such as br and img
© 2016 Pearson Education,
Inc., Hoboken, NJ. All rights
reserved. 24
HTML 5 Basic Structure
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8" />
<title>This is a title of the page</title>
</head>
<body>
<p>This is the content of the Web page
</body>
</html>
© 2016 Pearson Education,
Inc., Hoboken, NJ. All rights
reserved. 25
An HTML 5 DocumentOK to still follow the rules of XHTML
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8" />
<title>This is a title of the page</title>
</head>
<body>
<p>This is the content of the Web page.<br>
<img src="images/demo.png" alt="demo">
</p>
</body>
</html>
Arbitrary: cases for tags, pairing tags, uses of quotation marks.
Still a valid HTML 5 document.
<!doctype html>
<HtML lang=en>
<hEAd>
<meta charset=utf-8>
<TITLe>This is a title of the
page</tiTLE>
<boDY>
<P>This is the content of the
Web page.<br>
<IMg src=images/demo.png
alt=demo>
© 2016 Pearson Education,
Inc., Hoboken, NJ. All rights
reserved. 26
Easy to read Hard to read
Markup Validator
http://validator.w3.org/
to validate Web documents
© 2016 Pearson Education,
Inc., Hoboken, NJ. All rights
reserved. 27