HTML Attributes

Attributes provide additional information to an HTML element.
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HTML Tag Attributes
HTML tags can have attributes. Attributes provide additional information to an HTML element.
Attributes always come in name/value pairs like this: name="value".
Attributes are always specified in the start tag of an HTML element.

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Attributes Example 1:
Defines the start of a heading.
has additional information about the alignment.

Try it yourself: Center aligned heading

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Attributes Example 2:
Defines the body of an HTML document.

has additional information about the background color.

Try it yourself: Background color

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Attributes Example 3:
Defines an HTML table. (You will learn more about HTML tables later)

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Use Lowercase Attributes
Attributes and attribute values are case-insensitive. However, the World Wide Web Consortium (W3C) recommends lowercase attributes/attribute values in their HTML 4 recommendation, and XHTML demands lowercase attributes/attribute values.

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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 Tags

The most important tags in HTML are tags that define headings, paragraphs and line breaks.

The best way to learn HTML is to work with examples. We have created a very nice HTML editor for you. With this editor, you can edit the HTML source code if you like, and click on a test button to view the result.

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Try it Yourself - Examples
A very simple HTML document
This example is a very simple HTML document, with only a minimum of HTML tags. It demonstrates how the text inside a body element is displayed in the browser.

Simple paragraphs
This example demonstrates how the text inside paragraph elements is displayed in the browser.

(You can find more examples at the bottom of this page)

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Headings
Headings are defined with the <h1> to <h6> tags. <h1> defines the largest heading. <h6> defines the smallest heading.

<h1> This is a heading <h1>

This is a heading

<h2> This is a heading <h2>

This is a heading

<h3> This is a heading <h3>

This is a heading

<h4> This is a heading <h4>

This is a heading

<h5> This is a heading <h5>

This is a heading

<h6> This is a heading <h6>

This is a heading

HTML automatically adds an extra blank line before and after a heading.


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Paragraphs
Paragraphs are defined with the <p> This is a heading <h1> tag.
<p> This is a paragraph <p>

This is a paragraph

<p> This is another paragraph <p>

This is another paragraph

HTML automatically adds an extra blank line before and after a paragraph.

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Don't Forget the Closing Tag
You might have noticed that paragraphs can be written without end tags

:

<p> This is a paragraph
<p> This is another paragraph

The example above will work in most browsers, but don't rely on it. Future version of HTML will not allow you to skip ANY end tags.

Closing all HTML elements with an end tag is a future proof way of writing HTML. It also makes the code easier to understand (read and browse) when you to mark both where an element starts and where it ends.

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Line Breaks
The <br> tag is used when you want to break a line, but don't want to start a new paragraph. The <br> tag forces a line break wherever you place it.

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

Try it yourself

The <br> tag is an empty tag. It has no end tag like <br>, since a closing tag doesn't make any sense.

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<br> or <br/>
More and more often you will see the <br> tag written like this: <br/>

Because the <br> tag has no end tag (or closing tag), it breaks one of the rules for future HTML (the XML based XHTML), namely that all elements must be closed.

Writing it like <br/> is a future proof way of closing (or ending) the tag inside the opening tag, accepted by both HTML and XML.

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Comments in HTML
The comment tag is used to insert a comment in the HTML source code. A comment will be ignored by the browser. You can use comments to explain your code, which can help you when you edit the source code at a later date.
<!-- This is a comment -->


Note that you need an exclamation point after the opening bracket, but not before the closing bracket.

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Recap on HTML Elements
Each HTML element has an element name (body, h1, p, br)
The start tag is the name surrounded by angle brackets: <hr>
The end tag is a slash and the name surrounded by angle brackets </hr>
The element content occurs between the start tag and the end tag
Some HTML elements have no content
Some HTML elements have no end tag

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Basic Notes - Useful Tips
When you write HTML text, you can never be sure how the text is displayed in another browser. Some people have large computer displays, some have small. The text will be reformatted every time the user resizes his window. Never try to format the text in your editor by adding empty lines and spaces to the text.

HTML will truncate the spaces in your text. Any number of spaces count as one. Some extra information: In HTML a new line counts as one space.

Using empty paragraphs <p> to insert blank lines is a bad habit. Use the <br> tag instead. (But don't use the <br> tag to create lists. Wait until you have learned about HTML lists.)

HTML automatically adds an extra blank line before and after some elements, like before and after a paragraph, and before and after a heading.

We use a horizontal rule (the <hr> tag), to separate the sections in our tutorials.

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More Examples
More paragraphs
This example demonstrates some of the default behaviors of paragraph elements.

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

Poem problems
This example demonstrates some problems with HTML formatting.

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

Horizontal rule
This example demonstrates how to insert a horizontal rule.

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

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Basic HTML Tags
If you lookup the basic HTML tags in the reference below, you will see that the reference contains additional information about tag attributes.

You will learn more about HTML tag attributes in the next chapter 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
<p>Defines a paragraph
<br>Inserts a single line break
<hr>Defines a horizontal rule
<!--> Defines a comment

HTML Elements

HTML documents are text files made up of HTML elements.

HTML elements are defined using HTML tags.


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HTML Tags
HTML tags are used to mark-up HTML elements
HTML tags are surrounded by the two characters < and >
The surrounding characters are called angle brackets
HTML tags normally come in pairs like and
The first tag in a pair is the start tag, the second tag is the end tag
The text between the start and end tags is the element content
HTML tags are not case sensitive, means the same as

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HTML Elements
Remember the HTML example from the previous page:






This is my first homepage. This text is bold



This is an HTML element:

This text is bold

The HTML element starts with a start tag:
The content of the HTML element is: This text is bold
The HTML element ends with an end tag:

The purpose of the tag is to define an HTML element that should be displayed as bold.

This is also an HTML element:


This is my first homepage. This text is bold


This HTML element starts with the start tag , and ends with the end tag .

The purpose of the tag is to define the HTML element that contains the body of the HTML document.


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Why do We Use Lowercase Tags?
We have just said that HTML tags are not case sensitive: means the same as . If you surf the Web, you will notice that plenty of web sites use uppercase HTML tags in their source code. We always use lowercase tags. Why?

If you want to follow the latest web standards, you should always use lowercase tags. The World Wide Web Consortium (W3C) recommends lowercase tags in their HTML 4 recommendation, and XHTML (the next generation HTML) demands lowercase tags

HTML Introduction

What is an HTML File?
HTML stands for Hyper Text Markup Language
An HTML file is a text file containing small markup tags
The markup tags tell the Web browser how to display the page
An HTML file must have an htm or html file extension
An HTML file can be created using a simple text editor


Do You Want to Try It?
If you are running Windows, start Notepad.
If you are on a Mac, start SimpleText.
In OSX start TextEdit and change the following preferences: Open the the "Format" menu and select "Plain text" instead of "Rich text". Then open the "Preferences" window under the "Text Edit" menu and select "Ignore rich text commands in HTML files". Your HTML code will probably not work if you do not change the preferences above!



Type in the following text:





This is my first homepage. This text is bold


Save the file as "mypage.htm".



Start your Internet browser. Select "Open" (or "Open Page") in the File menu of your browser. A dialog box will appear. Select "Browse" (or "Choose File") and locate the HTML file you just created - "mypage.htm" - select it and click "Open". Now you should see an address in the dialog box, for example "C:\MyDocuments\mypage.htm". Click OK, and the browser will display the page.



Example Explained
The first tag in your HTML document is . This tag tells your browser that this is the start of an HTML document. The last tag in your document is . This tag tells your browser that this is the end of the HTML document.
The text between the tag and the tag is header information. Header information is not displayed in the browser window.
The text between the