Basic introduction to HTML elements

HTML documents are defined by HTML elements.

HTML Element Syntax

HTML element starts with a start tag

HTML element ends with an end tag

The content of the element is the sum of the start tag and the end tag Content between

Some HTML elements have empty content

Empty elements are closed in the start tag (end with the end of the start tag)

Large Most HTML elements can have attributes

Note: You will learn more about attributes in the next chapter of this tutorial.

Nested HTML Elements

38f82e2e6ee16e71259dc1f62a6b9774 element:

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

This e388a4556c0f65e1904146cc1a846bee element defines a paragraph in the HTML document.
This element has a start tag e388a4556c0f65e1904146cc1a846bee and an end tag 94b3e26ee717c64999d7867364b1b4a3.
The content of the element is: This is my first paragraph.

The 6c04bd5ca3fcae76e30b72ad730ca86d element:

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

The 6c04bd5ca3fcae76e30b72ad730ca86d element defines the body of the HTML document.
This element has a start tag 6c04bd5ca3fcae76e30b72ad730ca86d and an end tag 36cc49f0c466276486e50c850b7e4956. The
element content is another HTML element (p element).

The 100db36a723c770d327fc0aef2ce13b1 element:

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

The 100db36a723c770d327fc0aef2ce13b1 element defines the entire HTML document.
This element has a start tag 100db36a723c770d327fc0aef2ce13b1 and an end tag 73a6ac4ed44ffec12cee46588e518a5e.
The content of the element is another HTML element (body element).

Don’t forget the closing tag

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

e388a4556c0f65e1904146cc1a846beeThis is a paragraph
e388a4556c0f65e1904146cc1a846beeThis is a paragraph

The above example can also be displayed normally in the browser because the closing tag is optional.

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

HTML Empty Element

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

0c6dc11e160d3b678d68754cc175188a is an empty element without a closing tag (0c6dc11e160d3b678d68754cc175188a 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 df250b2156c434f3390392d09b1c9563, is the correct way to close an empty element, and is accepted by HTML, XHTML, and XML.

Even though 0c6dc11e160d3b678d68754cc175188a is valid in all browsers, using df250b2156c434f3390392d09b1c9563 is actually a longer-term guarantee.

HTML Tip: Use lowercase tags

HTML tags are not case-sensitive: 64e5601d0a941f4972a2954192bdae18 is equivalent to e388a4556c0f65e1904146cc1a846bee. Many websites use uppercase HTML tags.

W3CSchool uses lowercase tags because the World Wide Web Consortium (W3C) recommended lowercase in HTML 4 and will mandate lowercase in a future version of (X)HTML.

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