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

HTML documents are composed of nested HTML elements.

HTML document example

51e0250d38ff8209a41d24c7497d6fe4

The element defines the entire HTML document.
This element has a start tag and an end tag .
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:

This is a paragraph

This 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.

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
is valid in all browsers, using
is actually a longer-term guarantee.

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) recommended lowercase in HTML 4 and will mandate lowercase in a future version of (X)HTML.

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