Thursday, 6 May 2010

html

Example
<html>
<body>

<h1>My First Heading</h1>

<p>My first paragraph.</p>
</body>
</html>
What is HTML?

HTML is a language for describing web pages.

HTML stands for Hyper Text Markup Language

HTML is not a programming language, it is a markup language

A markup language is a set of markup tags

HTML uses markup tags to describe web pages

HTML Tags

HTML markup tags are usually called HTML tags

HTML tags are keywords surrounded by angle brackets like <html>

HTML tags normally come in pairs like <b> and </b>

The first tag in a pair is the start tag, the second tag is the end tag

Start and end tags are also called opening tags and closing tags

HTML Documents = Web Pages

HTML documents describe web pages

HTML documents contain HTML tags and plain text

HTML documents are also called web pages

The purpose of a web browser (like Internet Explorer or Firefox) is to read HTML documents

and display them as web pages. The browser does not display the HTML tags, but uses the

tags to interpret the content of the page:

<html>

<body>

<h1>My First Heading</h1>

<p>My first paragraph</p>




</body>

</html>

Example Explained

The text between <html> and </html> describes the web page

The text between <body> and </body> is the visible page content

The text between <h1> and </h1> is displayed as a heading

The text between <p> and </p> is displayed as a paragraph

What You Need

You don't need any tools to learn HTML at W3Schools.

  You don't need any HTML editor

  You don't need a web server

  You don't need a web site

Editing HTML

In this tutorial we use a plain text editor (like Notepad) to edit HTML. We believe this is the

best way to learn HTML.

However, professional web developers often prefer HTML editors like FrontPage or

Dreamweaver, instead of writing plain text.

Create Your Own Test Web

If you just want to learn HTML, skip the rest of this chapter.

If you want to create a test web on your own computer, just copy the 3 files below to your

desktop.

(Right click on each link, and select "save target as" or "save link as")

page1.htm

page2.htm

After  you have copied the files, you can double-click on the file called "mainpage.htm" and

see your first web site in action.

Use Your Test Web For Learning

We suggest you experiment with everything you learn at W3Schools by editing your web

files with a text editor (like Notepad).

Note: If your test web contains HTML markup tags you have not learned, don't panic. You

will learn all about it in the next chapters.

HTM or HTML Extension?

When you save an HTML file, you can use either the .htm or the .html extension. We use

.htm in our examples. It is a habit from the past, when the software only allowed three letters

in file extensions.




With new software it is perfectly safe to use .html.

Don't worry if the examples use tags you have not learned.

You will learn about them in the next chapters.

HTML Headings

HTML headings are defined with the <h1> to <h6> tags.

Example

<h1>This is a heading</h1>

<h2>This is a heading</h2>

<h3>This is a heading</h3>

HTML Paragraphs

HTML paragraphs are defined with the <p> tag.

Example

<p>This is a paragraph</p>

<p>This is another paragraph</p>

HTML Links

HTML links are defined with the <a> tag.

Example

<a href="http://www.w3schools.com">This is a link</a>

Note: The link address is provided as an attribute.

(You will learn about attributes in a later chapter of this tutorial)

HTML Images

HTML images are defined with the <img> tag.

Example

<img src="w3schools.jpg" width="104" height="142" />




Note: The name and the size of the image are provided as attributes.

(You will learn about attributes in a later chapter of this tutorial)

HTML Basic - 4 Examples

Don't worry if the examples use tags you have not learned.

You will learn about them in the next chapters.

HTML Headings

HTML headings are defined with the <h1> to <h6> tags.

Example

<h1>This is a heading</h1>

<h2>This is a heading</h2>

<h3>This is a heading</h3>

HTML Paragraphs

HTML paragraphs are defined with the <p> tag.

Example

<p>This is a paragraph</p>

<p>This is another paragraph</p>

HTML Links

HTML links are defined with the <a> tag.

Example

<a href="http://www.imraninfo.co.cc">This is a link</a>




Note: The link address is provided as an attribute.

(You will learn about attributes in a later chapter of this tutorial)

HTML Images

HTML images are defined with the <img> tag.

Example

<img src="w3schools.jpg" width="104" height="142" />

Note: The name and the size of the image are provided as attributes.

(You will learn about attributes in a later chapter of this tutorial)

HTML Elements

HTML documents are defined by HTML elements.

HTML Elements

An HTML element is everything from the start tag to the end tag:

Start tag * Element content End tag *

<p>

 This is a paragraph </p>

<a href="default.htm"

 This is a link </a>

> 

<br />

 

 

* The start tag is often called the opening tag. The end tag is often called the closing tag.

HTML Element Syntax

An HTML element starts with a start tag / opening tag

An HTML element ends with an end tag / closing tag

The element content is everything between the start and the end tag

Some HTML elements have empty content

Empty elements are closed in the start tag

Most HTML elements can have attributes




(You will learn about element attributes in the next chapter of this tutorial)

Nested HTML Elements

Most HTML elements can be nested (can contain other HTML elements).

HTML documents consist of nested HTML elements.

HTML Document Example

<html>

<body>

<p>This is my first paragraph</p>

</body>

</html>

The example above contains 3 HTML elements.

Example Explained

The <p> element:

<p>This is my first paragraph</p>

The <p> element defines a paragraph in the HTML document

The element has a start tag <p> and an end tag </p>

The element content is: This is my first paragraph

The <body> element:

<body>

<p>This is my first paragraph</p>

</body>

The <body> element defines the body of the HTML document

The element has a start tag <body> and an end tag </body>

The element content is another HTML element (a paragraph)

The <html> element:

<html>

<body>

<p>This is my first paragraph</p>

</body>

</html>

The <html> element defines the whole HTML document.

The element has a start tag <html> and an end tag </html>

The element content is another HTML element (the body)




Don't Forget the End Tag

Most browsers will display HTML correctly even if you forget the end tag:

<p>This is a paragraph

<p>This is a paragraph

The example above will work in most browsers, but don't rely on it. Forgetting the end tag

can produce unexpected results or errors.

Note: Future version of HTML will not allow you to skip end tags.

Empty HTML Elements

HTML elements without content are called empty elements. Empty elements can be closed in

the start tag.

<br> is an empty element without a closing tag (it defines a line break).

In XHTML, XML, and future versions of HTML, all elements must be closed.

Adding a slash to the start tag, like <br />, is the proper way of closing empty elements,

accepted by HTML, XHTML and XML.

Even if <br> works in all browsers, writing <br /> instead is more future proof.

HTML Tip: Use Lowercase Tags

HTML tags are not case sensitive: <P> means the same as <p>. Plenty of web sites use

uppercase HTML tags in their pages.

W3Schools use lowercase tags because the World Wide Web Consortium (W3C)

recommends lowercase in HTML 4, and demands lowercase tags in future versions of

(X)HTML.

HTML Attributes

Attributes provide additional information about HTML elements.

HTML Attributes

HTML elements can  have attributes

Attributes provide additional information about the element

Attributes are always specified in the start tag

Attributes come in name/value pairs like: name="value"

Attribute Example




HTML links are defined with the <a> tag. The link address is provided as an attribute:

Example

<a href="http://www.w3schools.com">This is a link</a>

(You will learn about links in a later chapter of this tutorial)

Always Quote Attribute Values

Attribute values should always be enclosed in quotes.

Double style quotes are the most common, but single style quotes are also allowed.

In some rare situations, like when the attribute value itself contains quotes, it is necessary to

use single quotes:

name='John "ShotGun" Nelson'

HTML Tip: Use Lowercase Attributes

Attribute names and attribute values are case-insensitive.

However, the World Wide Web Consortium (W3C) recommends lowercase

attributes/attribute values in their HTML 4 recommendation

Newer versions of (X)HTML will demand lowercase attributes.

HTML Attributes Reference

A full list of legal attributes for each HTML element is listed in our:

Complete HTML Reference

Below is a list of some attributes that are standard for most HTML elements:

Attribute Value

 Description

class class_rule or style_rule The class of the element

id id_name

 A unique id for the element

style style_definition An inline style definition

title tooltip_text  A text to display in a tool tip

For more information about standard attributes:

HTML Standard Attributes Reference




Your browser does not support inline frames or is currently configured not to

display inline frames.

HTML Headings

Headings are important in HTML documents.

HTML Headings

Headings are defined with the <h1> to <h6> tags.

<h1> defines the largest heading. <h6> defines the smallest heading.

Example

<h1>This is a heading</h1>

<h2>This is a heading</h2>

<h3>This is a heading</h3>

Note: Browsers automatically adds an empty line before and after headings.

Headings Are Important

Use HTML headings for headings only. Don't use headings to make text BIG or bold.

Search engines use your headings to index the structure and content of your web pages.

Since users may skim your pages by its headings, it is important to use headings to show the

document structure.

H1 headings should be used as main headings, followed by H2 headings, then less important

H3 headings, and so on.

HTML Rules (Lines)

The <hr /> tag is used to create an horizontal rule (line).

Example

<p>This is a paragraph</p>

<hr />

<p>This is a paragraph</p>

<hr />




<p>This is a paragraph</p>

HTML Comments

Comments can be inserted in the HTML code to make it more readable and understandable.

Comments are ignored by the browser and are not displayed.

Comments are written like this:

Example

<!-- This is a comment -->

Note: There is an exclamation point after the opening bracket, but not before the closing

bracket.

HTML Tip - How to View HTML Source

Have you ever seen a Web page and wondered "Hey! How did they do that?"

To find out, click the VIEW option in your browser's toolbar and select SOURCE or PAGE

SOURCE. This will open a window that shows you the HTML code of the page.

Examples From This Page

Headings

This example demonstrates the tags that display headings in an HTML document.

Hidden comments

This example demonstrates how to insert a hidden comment in the HTML source code.

Horizontal rule

This example demonstrates how to insert a horizontal rule.

HTML Tag Reference

W3Schools' tag reference contains additional information about these tags and their 

attributes.

You will learn more about HTML tags and attributes in the next chapters of this tutorial.

Tag

 Description

<html>

 Defines an HTML document




<body>

 Defines the document's body
<h1> to <h6> Defines header 1 to header 6
<hr />
 Defines a horizontal rule

<!-->

 Defines a comment

HTML documents are divided into paragraphs.

HTML Paragraphs

Paragraphs are defined with the <p> tag.

Example

<p>This is a paragraph</p>

<p>This is another paragraph</p>

Note: Browsers automatically adds an empty line before and after paragraphs.

Don't Forget the End Tag

Most browsers will display HTML correctly even if you forget the end tag:

Example

<p>This is a paragraph

<p>This is another paragraph

The example above will work in most browsers, but don't rely on it. Forgetting the end tag

can produce unexpected results or errors.

Note: Future version of HTML will not allow you to skip end tags.

HTML Line Breaks

Use the <br /> tag if you want a line break (a new line) without starting a new paragraph:

Example

<p>This is<br />a para<br />graph with line breaks</p>




The <br /> element is an empty HTML element. It has no end tag.

<br> or <br />

In XHTML, XML, and future versions of HTML, HTML elements with no end tag (closing

tag) are not allowed.

Even if <br> works in all browsers, writing <br /> instead is more future proof.

HTML Output - Useful Tips

You cannot be sure how HTML will be displayed. Large or small screens, and resized

windows will create different results.

With HTML, you cannot change the output by adding extra spaces or extra lines in your

HTML code.

The browser will remove extra spaces and extra lines when the page is displayed. Any

number of lines count as one space, and any number of spaces count as one space.

Try it yourself 

(The example demonstrates some HTML formatting problems)

Examples From This Page

HTML paragraphs

This example demonstrates how HTML paragraphs are displayed in a browser.

Line breaks

This example demonstrates the use of line breaks in an HTML document.

Poem problems

This example demonstrates some problems with HTML formatting.

More Examples

More paragraphs

This example demonstrates some of the default behaviors of paragraph elements.

HTML Tag Reference

W3Schools' tag reference contains additional information about HTML elements and their

attributes.

Tag Description
<p> Defines a paragraph
<br /> Inserts a single line break













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