HTML vs XHTML: The Differences You Should Know

HTML 5 | December 26, 2022
HTML vs XHTML

The full form of HTML is Hyper Text Markup Language, derived from SGML, whereas XHTML is also called eXtensible Hyper Text Markup Language, derived from XML. Expansions for XHTML and HTML include eXtensible Markup Language, derived from XML, and HyperText Markup Language, derived from SGML. These two programming languages are utilized in developing web pages and web applications. HTML differs from the fundamental features in that it employs plain text formatted code, is case-sensitive, and is less expensive. While more expensive than HTML and not case-sensitive, XHTML utilizes XML as the application code. But is this the only way they differ or are there other essential aspects? To learn more, let’s compare HTML vs XHTML.

Markup Languages: What Are They?

The core capabilities needed to build a website are markup languages. Each webpage shows the user some text, graphics, or structured data. The markup of a website is determined by how the user is presented with textual or graphic information. Various fonts for different terms, colors for different kinds of text, and so on may be necessary while building a HTML website from PSD file. We also demand universality in the markup, meaning that the website must be identical in all browsers. It necessitates the usage of a standardized markup language so that information may be presented to users via web pages.

What is the difference between HTML Vs XHTML?

The first webpage ever created was created using the markup language HTML. Since the creation of this website, the HTML language has undergone numerous revisions and variations, including the addition of the idea of error handling and new features like tables, resulting in XHTML. Building applications for the web and Android requires the use of both languages. Extensible Hypertext Markup Language (XHTML) is a subset of Hyper Text Markup language (HTML). It is an extension of HTML and is more rigid and organized than HTML. Let’s see some of the differences between these two markup languages:

Hyper Text Markup Language (HTML)eXtensible Hyper Text Markup Language (XHTML)
It is a Standard Generalized Markup Language (SGML) based language.It is an eXtensible markup language (XML) based language.
It is not a case-sensitive language.It is a case-sensitive language.
HTML empty elements do not require any closing symbol to indicate the end of the tag.XHTML empty elements always need to be closed using the ‘/’ symbol.
In HTML, it is not mandatory to use quotes for using attributes.In XHTML, it is mandatory to use quotes for using attributes.
The file has an extension of .html or.htmThe file has an extension of .xhtml, .xht, or .xml
It requires a minimum of 4 tag declarations, i.e., <HTML>, <head>, <title>, and <body>. The declaration of <!Doctype> is not compulsory.It requires a minimum of 5 tag declarations, i.e.,<!Doctype>,  <HTML>, <head>, <title>, and <body>.
It has relatively less strict error handling.It has relatively strict error handling

Head to-Head Comparison between HTML and XHTML

The top eight comparisons between HTML and XHTML are listed below:

ParametersHTMLXHTML
AbbreviationHyper Text Markup LanguageeXtensible Hyper Text Markup Language
Case- SensitiveNoYes
Internet media typeHTML/textapplication/XHTML+XML
ExpressiveLess ExpressiveMore Expressive
FormatDocument file formatMarkup language file format
Parser RequiredRequires lenient HTML specific parserRequires standard XML parser
ConstraintNo well-formed constraintsWell-formed constraints
DerivationIt is a derivation of SGMLIt is derived from XML

Examples

The tables above list several differences, which we will examine in-depth here with the use of examples.

1. A Document in XHTML with the Minimum Necessary Tags

First, an XHTML document needs to contain the <!DOCTYPE> declaration. The document also has to include the <html>, <head>, <title>, and <body> tags.

Additionally, the xmlns attribute in <html> must specify the document’s XML namespace.

Let’s look at it using an example:

<!DOCTYPE html PUBLIC “-//W3C//DTD XHTML 1.1//EN”
“http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd”>
<html xmlns=“http://www.w3.org/1999/xhtml”>
<head>
  <title>Example of xhtml page</title>
</head>
<body>

It is a random line

</body>
</html>

2. In XHTML, Empty Elements Should Always be Closed.

Elements that have nothing between them are said to be empty elements. Since these tags lack a closing tag, they must instead be ended with the slash (/) character.

Those tags are used to make changes to the webpage, such as adding an image or a horizontal line.

Let’s look at them using an example.

<img src=“google.jpg” alt=“google” />
We welcome you!

3. XHTML is case-sensitive.

The attributes in XHTML should always occur in lower-case letters as it would treat lower and upper-case letters differently. For example

<div>
<p> Hey there! How are you> </p>
</div>

Here, the code is correct as p and div are in lowercase but would be incorrect if they were in uppercase forms.

4. The XHTML Element Must Be Nested Correctly

Every XHTML element must be properly nested, which means it must be closed in the exact order it was opened.

Let’s look at an example of it.

<b><i> Hope you are good. </i></b>

The above example has the correct format, as the tags are opening and closing in the same order. If the <b> tag had closed before <i>, it would be considered wrong.

Benefits? Use the right tool for the right job.

Is there a benefit to using one HTML version over another? There is no simple solution, and the advantages you will experience depend on the situation and the language used. Although there are few obvious benefits for your website’s viewers when you move from HTML to XHTML, there are still several compelling authoring-side arguments in favor of doing so:

1. Easy maintenance

Since the structure is much more obvious, and mismatched tags are easier to notice, XHTML is simpler to code and maintain since it corresponds to the XML grammar standards, which require that every opened tag be closed.

2. Future-ready

XHTML 1.0 pages will be easily upgradeable to the new version of XHTML once it becomes a recommendation, enabling them to benefit from its exciting new capabilities. By that time, you can likely convert your XHTML 1.0 (strict) pages to XHTML 2.0 documents with an XSLT style sheet.

3. Easy to learn 

Compared to the SGML standards on which HTML is based, the syntactic rules specified by XML are now more consistent and, as a result, simpler to explain. The CSS Box Model is also made easier to explain.

4. XSL-ready

HTML 4.01 has been rebuilt in XML as XHTML 1.0. As a result, XHTML documents are both XML documents and hypertext documents—extensible Style Sheets (XSL). Language Transformations, a powerful tool for manipulating and transforming XML documents, was created at W3C. This technology is helpful for automatically producing various additional resources from an XHTML document.

Conclusion

The syntax given by XHTML provides several significant advantages, but the importance of these advantages must be assessed in the context of your project; in other words, use the appropriate tool for the appropriate task. In daily usage, HTML is just as valuable as XHTML.

Adopting XHTML could be advantageous for a web designer in some situations and will undoubtedly facilitate future negotiations. Without learning new semantics, XHTML provides an excellent opportunity to learn about XML languages and their potential. It is a reasonable method of developing one’s competencies without much effort.