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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.).

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Inside Ooligan Press: What Does an Editor Do?

Note: This is part of the blog series “Inside Ooligan Press,” about how we take a manuscript from an idea to a professionally published book.

There are many levels of editing that help shape a manuscript into what readers ultimately pull off the shelves of their favorite bookstore or library, but how does each level of editing work to transform a manuscript from the first draft to the final, polished result?

As editors, we create and manage all editorial timelines and guide an author through the publishing process as their manuscript undergoes multiple levels of editing. In addition, an editor’s goal is to help an author strengthen their writing while also maintaining their voice and overall tone of their story. To do this, editors follow guidelines set by the client they are working with, the publishing house they work within, and style guides used across particular industries. Here at Ooligan Press, we utilize our house-made style guide and a style guide created specifically for each manuscript we publish, as well as the Chicago Manual of Style (CMOS) that is broadly used across the publishing industry. These guides encompass standard rules for the treatment of numbers, the use of commas, and the use of other punctuation, as well as citations and endnotes when applicable.

CMOS is the standard style guide used in trade book publishing, but each publishing house may also utilize an internal style guide for specific editorial decisions. For example, at Ooligan, our style guide has a specific section for inclusivity that we reference to ensure our publications are accessible to readers and use inclusive language. We also create style guides for each manuscript to address book-specific editing choices such as the spelling of unique names and phrases, often seen in fantasy or non-fiction books.

These style guides are utilized throughout the four main editing stages: developmental editing, copyediting, line editing, and proofreading. The first round of editing that a manuscript goes through is developmental editing, also called a DE. This round is undertaken by our Acquisitions Department, who work with authors to complete big picture editing. Rather than correcting spelling errors or comma splices at this stage, a DE looks at the manuscript from the top down, addressing plot holes, character development, and plot points that move the story forward.

After Acquisitions receives these big picture edits back from the author, the manuscript is handed off to our Managing Editor to guide the manuscript through more specific edits. Manuscripts we acquire generally go through two rounds of copyediting, one heavy copyedit and one light-to-medium copyedit, depending on what each manuscript needs. These rounds of edits look for spelling mistakes, errors in punctuation, and smaller, more specific story edits as needed. Story edits are marked in comments as queries to the author to point them in the right direction if there is any confusion within the manuscript. For these types of queries, our editors explain why they are bringing something to the author’s attention and provide at least two suggestions that would provide more clarity. Like during a DE, these suggestions are up to the discretion of the author and aim to maintain their voice. Alongside these suggestions and correcting punctuation and spelling, we also strive to correct grammatical errors and sentence structure, a process called line editing. Here we look at each sentence and its role within the manuscript. Awkward wording is flagged and suggestions are provided to help the author rework unclear sentences.

Following these copyedits, the manuscript is sent to the Design Department to transform the Word Document into a designed PDF that will ultimately turn into the final published book. But before this designed interior can be sent to the printers, it must undergo one last round of editing to ensure all errors are corrected. We call this round a print proofread, in which editors compare the designed interior to the most recently edited Word Document. Here we make sure that there are no missing paragraphs or sections, all punctuation and italics are correct, and no stray code made its way into the manuscript during the design process. Once the proofread is complete, the book is sent to the printers and the final book is produced. In a similar fashion to print proofreads, we also perform ebook proofreads to ensure a digital copy of the manuscript is formatted correctly and no errors were introduced during coding.

While these are the editorial steps we undertake at Ooligan, each publishing house may differ from these steps depending on their department structure. No editing schedule is the end-all be-all for editing, but a good editor will work directly with an author to maintain their vision for their manuscript. The most important job an editor undertakes is helping an author create the best version of their manuscript and strengthen their writing while maintaining their unique voice.

the word "proofread" followed check boxes that say "grammar," "formatting," and "spelling"

The Dos and Don’ts of Proofreading

The topic of copyediting is talked about at length within the publishing industry, but there is little discussion about another aspect of the editorial process that is equally as important: proofreading. Here is a quick guide to everything you need to know about proofreading your next project.

Proofreading is one of the last steps in the editorial process. The manuscript has completed all rounds of copyediting, has been XML typecoded, and has been sent to the designer to complete the interior. The book is nearly complete and just needs a final check to ensure that errors weren’t introduced during the design process and that there are no lingering grammatical errors. Proofreading is the final step before the book is sent to the printer, but there is much confusion about what is and is not covered during this stage of editing.

Here are some things to look for as you complete your next proofread:

Weird Spacing:

Be on the lookout for missing spaces between words or punctuation and places where there are additional spaces where there shouldn’t be.

Leftover XML Coding:

At Ooligan, our books are XML typecoded so that the designer knows what special treatment different words and sections should have. Sometimes parts of this code accidentally make its way into the final manuscript, so be on the lookout for erroneous code.


Double-check that everything from the final version of the manuscript has been included in the designed version. Check for missing paragraphs or words, missing images or graphics, or missing punctuation marks.


As you are proofreading, check the punctuation surrounding words that are in bold or italics—do they follow the guidelines outlined in your style guide? Also be on the lookout for placement of punctuation within quotations—do they follow the guidelines outlined in your style guide?

Closed vs. Open Compounds:

Make sure that compounds are following the Hyphenation Guide for Chicago.

Consistent Spelling:

Be on the lookout for names, places, and other words that may be spelled inconsistently throughout the manuscript. We recommend keeping the style sheet for the book nearby as you proofread.


Double-check that all ellipses are formatted according to the style guide. For Chicago, it is three periods with spaces: . . .

Windows, Runts, and Orphans:

Be mindful of the way paragraphs start and end. Widows happen when the last line of a paragraph starts at the top of the next page. Runts occur when the last line of a paragraph ends with a single word. Orphans happen when the first line of a paragraph is on the bottom of a page.

Here are some things to keep in mind when completing a proofread. The time for any substantial editing is over. Now is the time to look for any glaring errors that are remaining after the copyedits are completed. We don’t want to be rewriting any of the text or posing queries to the author—there shouldn’t be any substantial changes to the manuscript at this stage.

I hope this guide helped shed some light on what is expected—and what to avoid—for your next proofread.

Happy proofreading!