Some of the most commonly used terms in web design and development are HTML, HTML5 and XHTML. Still, those who are new the web, often admit to have difficulty telling the difference between HTML vs HTML5 vs XHTML. Additionally, there is often confusion as to which one of these languages to start learning for a novice.
There is no wonder such confusion persists — all three are markup languages, performing, essentially, the same task. For those who would like to know more about this topic, this post will further clarify the main terms in more detail.
Understanding markup languages
A markup language is a fundamental tool that facilitates creation of any webpage. If a webpage needs to display some structured information, such as text or images, then the markup of this webpage is the means to do so. The process and practice of web design normally suggests that different parts of text are displayed with different features applied to them — font, size, colour etc.
Meanwhile, there is also a need for comprehensive markup, in order for a webpage to look and perform in the same way no matter what browser it is viewed in. This creates the demand for a common markup language to conveniently display the necessary information.
Markup languages consist of smaller building blocks — tags — that allow to display data in the right format. Tags handle the way the information on a webpage is displayed — from subtle visual features to the overall structure of the page. There are specific tags to define such webpage elements as header, body, paragraph, and many more.
HTML and HTML5
A markup language most common today, is HTML. It was designed by the inventor of the World Wide Web himself — Tim Berners-Lee. The name — HTML — is an abbreviation, which stands for HyperText Markup Language, and it was the first markup language used to build and display web pages.
Soon after creation, HTML saw rapid development, and its subsequent versions became a standard for markup languages. Over time it evolved through a number of milestone versions, however, all of these up to HTML4 are commonly referred to just as HTML. This draws a line between earlier versions, and the next and currently the latest version of HTML – HTML5 – emphasising a significant difference between them.
It is worth noting that before HTML5 was released, the World Wide Web Consortium (W3C) initiated work to develop an extension of the basic HTML, merging it with XML format. This was meant to resolve some compatibility issues that browsers were experiencing at the time.
HTML and XML are both standard markup languages, very similar in function. However, the latter is different in that it is stricter in handling errors and formatting. The language that came to be as a result still showed a great resemblance to HTML4, but introduced some additional, more rigorous rules. It was named XHTML.
Differences between HTML vs XHTML vs HTML5
We have looked at the function and evolution of these three markup languages, so it is now time to explore the specific differences between them in more depth.
HTML vs HTML5
Created by a group called WHATWG, HTML5 was intended as an improvement over the older versions of HTML, meant to solve some of the existing cross-browser compatibility problems. Listed below are some of the main differences between HTML and HTML5:
- HTML5 provides better support for different types of media – for example, audio and video. It is done by providing additional tags for media files. By contrast, HTML doesn’t support these tags and, instead, depends on third-party plugins.
- HTML5 introduced brand-new input attributes, including email, URLs, date and time, and search, to name a few.
- HTML5 has better browser compatibility than HTML. It is also device independent.
- HTML5 adopts superior text processing rules, also known as parsing. This allows for much greater parsing flexibility than HTML.
- HTML5 now makes it a lot easier to find locations without the need for third-party plugins.
- HTML5 provides native support for vector graphics. This reduces the need for third-party software, such as Adobe Flash.
In simple terms, the newly introduced features make HTML5 a better version of HTML, upgraded with new features and functionalities.
HTML vs XHTML
XHTML is, basically, an extension to HTML. You can think of it as an updated, stricter version of HTML4. Therefore, there aren’t too many differences between the two. Below we have listed some of the most notable ones:
- HTML accepts that some elements may not contain the closing tag. XHTML expects that all elements with no exception include a closing tag. (Note: A closing tag is added at the end of an element, such as a paragraph. They usually consist of the name of the element preceded by a backslash. Thus, an opening tag for a paragraph is <p>, and the closing tag is </p>)
- XHTML, unlike HTML does not allow elements to overlap.
- XHTML requires that all attribute values (e.g., font size) are quoted – even the numeric ones. There is no such requirement in HTML.
- For a document to be valid XHTML, attributes cannot be minimised.
- There are also some minor differences in the way both languages handle empty elements.
The differences mentioned above are some of the most obvious ones. The full list is substantially longer, however, it, by a large margin, consists of features too subtle to encounter on a daily basis. These can be further explored by referring to XHTML documentation. The key thing to remember is that XHTML was developed to fix some shortcomings of HTML by introducing certain features of XML.
HTML5 vs XHTML
As you already know, XHTML and HTML are very similar, meaning that most differences between HTML and HTML5 also apply to HTML5 and XHTML. However, there is some further variation between the two:
- XHTML is case sensitive (same as HTML), whereas HTML5 is not.
- Both XHTML and HTML have a more complex doctype than HTML5. (Note: doctype tells browsers how to interpret the data.)
- HTML5 is compatible with all browsers. XHTML is not.
- HTML5, being a successor of HTML, is much more flexible than XHTML.
- XHTML is better suited for desktop computers, while HTML5 is better suited for mobile devices — smartphones and tablets.
To summarise, all three – HTML, HTML5 and XHTML are markup languages, each possessing a particular subset of features. Both XHTML and HTML5 were developed as improved versions of HTML4. XHTML was designed to incorporate some features of XML, while with the development of HTML5 we saw a range of significant improvements that make it the best markup language of the three, and by far the most widely used one today.
An important takeaway is that all three languages are just variations of the same HTML standard, but incorporating different syntactic rules and features. To those who are making their first steps in web design it is recommended to skip XHTML and HTML4, and proceed with learning HTML5 instead because of its widespread use and enhanced functionality.