Detailed introduction to HTML elements

HTML documents are defined by HTML elements.

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HTML elements

Start tag *	Element content	End tag *
	This is a paragraph
	This is a link

*The opening tag is often called opening tag, and the ending tag is often called closing tag.

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HTML Element Syntax

• HTML elements start with tags start with

• 
  

• ## HTML elements end with the

  tag terminated

• 
  

## The content of the
• element

  is the content between the start tag and the end tag

• 
  

Some HTML elements have
• empty content

• 
  

Empty elements
• are closed in the opening tag

  (end with the end of the opening tag)

• 
  

  ## Most HTML elements can have the
• attribute

Comments

: You will learn more about properties in the next chapter of this tutorial. Nested HTML elements

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HTML documents are composed of nested HTML elements.

HTML document example

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This is my first paragraph.

The above example contains three HTML elements.

HTML example analysis

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The

element:

This is my first paragraph.

The

element defines a paragraph in an HTML document.

This element has an opening tag

and an ending tag

.

The element content is: This is my first paragraph.

The element:

This is my first paragraph.

The element defines the body of the HTML document.
This element has an opening tag and an ending tag .

The element content is another HTML element (the p element).

The element:

This is my first paragraph.

The element defines the entire HTML document.
This element has an opening tag and an ending tag .
The element content is another HTML element (the body element).

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Don’t forget the closing tag

Even if you forget to use the closing tag, most browsers will display the HTML correctly:

This is a paragraph

This is a paragraph

The above example also displays fine in the browser because closing the tag is optional.

But don't rely on this approach. Forgetting to use a closing tag can produce unpredictable results or errors.

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HTML empty element

An HTML element with no content is called an empty element. Empty elements are closed in the opening tag.

is an empty element without a closing tag (
tag definition wraps).

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

Adding a slash in the opening tag, such as
, is the correct way to close an empty element, and is accepted by HTML, XHTML, and XML.

Even though
works in all browsers, using
is actually safer in the long run.

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HTML Tip: Use lowercase tags

HTML tags are not case-sensitive:

is equivalent to

. Many websites use uppercase HTML tags.

W3CSchool uses lowercase tags because the World Wide Web Consortium (W3C) recommends the use of lowercase in HTML 4, and will mandatory use it in future (X)HTML versions lower case.

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