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XML, HTML, CSS, and XHTML: Definitions and Uses

The digital side of the publishing industry (and of any industry) includes a lot of acronyms, especially when referring to coding. You have probably heard or read about XML, HTML, CSS, and XHTML. But do you know what they mean? Have you ever wondered how they are used?

In today’s blog post, we will go over what all those acronyms mean and how we use them at Ooligan Press.

XML, HTML, and XHTML are markup languages, which means that they are “a system for marking or tagging a document that indicates its logical structure and gives instructions for its layout on the page especially for electronic transmission and display.” In contrast, CSS is “the language we use to style a Web page.”

A lot of other languages exist for different programs and goals. We will only go over the four mentioned above because they are the ones that are most often used in the publishing industry. Before going into what they are used for, here are their definitions:

  • XML (Extensible markup language) is “a simple text-based format for representing structured information.”
  • HTML (Hypertext Markup Language) is “the standard markup language for Web pages.” Through tags and elements, this language describes the structure of the page and tells “the browser how to display the content.”
  • CSS (Cascading Style Sheets) is a markup language that “describes how HTML elements are to be displayed” and is used as a way to “control the layout of multiple web pages all at once.”
  • XHTML (Extensible Hypertext Markup Language) “is a stricter, more XML-based version of HTML” that “was developed to make HTML more extensible and flexible to work with other formats.”

All these coding languages have standards and rules that are followed by everyone. From the definitions provided, we can see how XML, HTML, and XHTML are languages used to describe and define the context, while, in contrast, CSS is a language only used to define the style of that content.

At Ooligan Press, we use these three markup languages and one style sheet for different tasks.

The first markup language we encounter within the book production process is XML. After the manuscript is copyedited and, therefore, we have the final document, the text goes through typecoding with XML. This step comes right before the document is sent to the designer and it is used to make their work easier. The designer will grab the XML file and import it to InDesign. The tagged text helps them know where special circumstances in the text happen, such as bold or cursive text.

Once the designer finishes the manuscript, we have the final print version. This is sent to the digital manager who will export it to epub. In order to code and style the epub file, which is done to correct and polish the final ebook, they use XHTML and CSS. All the text in the ebook is tagged with XHTML and styled with CSS.

Another markup language we use is HTML. We mainly use it to tag our blog posts so that the Online Content Manager only has to copy and paste the text, and the editor in WordPress will automatically adjust it.

Having experience in these coding languages is certainly a good skill to have within the publishing industry. And there are a lot of resources available on the Internet to self-teach the basics. The most reliable resource is W3Schools, which offers definitions, explanations, and tutorials to learn different languages (such as HTML, Python, CSS, etc.).