HTML allows for certain elements to be "void," meaning they don’t require a closing tag. A common example is the line break element, <br>. However, you might encounter different ways to write this tag: <br>, <br/>, or <br />. This tutorial will clarify the proper usage and historical context of these variations.
What are Void Elements?
Void elements, by definition, do not have content between a start and end tag. They represent content that doesn’t contain other content. Examples include <br>, <hr>, <img>, <input>, and <meta>.
HTML5 and Void Element Syntax
In HTML5, the simplest form, <br>, is perfectly valid. The HTML5 specification allows for void elements to be written without a trailing slash. This is the preferred and most concise way to write them.
However, the specification also explicitly allows for the inclusion of a forward slash before the closing bracket – <br/> or <br />. This is done to maintain compatibility with XHTML, a stricter, XML-based version of HTML.
Why the Variations?
Historically, the different forms emerged due to the transition from HTML 4 to XHTML.
- HTML 4: Void elements like
<br>were acceptable without a trailing slash. - XHTML: XHTML, being based on XML, requires all tags to be closed. This led to the
<br/>or<br />syntax. The space before the forward slash was sometimes recommended for older browser compatibility, but it’s generally not essential.
Which one should you use?
For modern HTML5 development, <br> is the preferred and recommended form. It’s the simplest, most readable, and perfectly valid according to the specification.
Using <br/> or <br /> won’t break your code, but it’s unnecessary unless you specifically need to ensure compatibility with very old systems or are working within an environment that enforces XHTML-style syntax.
Example:
<p>This is the first line of text.<br>
This is the second line of text.</p>
<p>This is the first line of text.<br/>
This is the second line of text.</p>
<p>This is the first line of text.<br />
This is the second line of text.</p>
All three examples will render the same output in modern browsers.
Key Takeaway: While multiple forms are valid, prioritize simplicity and adhere to modern HTML5 practices by using <br> whenever possible. Understanding the historical context explains why you might encounter the other forms, but they are not necessary for current development.