I hope nobody took the previous post too seriously. It was meant as a satirical joke, pointing out several shortcomings of the notorious LaTeX vs. Word comparison study. I still want to say a few things on the topic, though; and this time I’m completely serious.

I realize that LaTeX can be daunting for scientists who have little programming (or, more generally, computer science) background, to the point that they may well opt for user-friendlier alternatives. I cannot deny that knowing one’s way around LaTeX requires some time; and, until they reach a good level, LaTeX users may be slowed down and ineffective. However, I think it is important to at least understand why LaTeX remains predominant in scientific publishing; that is, what benefits come after a sufficient investment in learning to use it. If you have the same background I have, this post will probably sound completely obvious. Otherwise, read on.

The key features of LaTeX as a document preparation system are:

1. LaTeX is a markup language, that is it consists of annotations combined with the actual content to be displayed; the annotations define structure and appearance of the content, but both are expressed as plain text.
2. LaTeX is a set of commands that translate down to TeX and Metafont.

Both features contribute to the user unfriendliness of LaTeX compared to so-called WYSIWYG document preparation systems such as Word; but also are what makes LaTeX superior in practically every other aspect. To put it in concrete terms: I think it’s entirely possible that LaTeX will eventually be replaced, for scientific publishing, by a different document preparation system (Markdown extensions anyone?). But, if this will ever happen, the replacement system will certainly be another markup language; and will very likely translate down to TeX and Metafont.

Why markup languages are better

Markup languages, where all information is encoded in plain text, are naturally amenable to editing using a whopping variety of tools that also operate on text files. Your favorite text editor — including Word itself, if you insist — is also a LaTeX editor, with spell checking and all other functionalities readily available. Text manipulation tools based on regular expressions — grep, sed, awk, perl, you name it — are directly applicable to LaTeX texts. Data processing environments — such as R for statistical analysis — can easily export data to LaTeX since all they have to produce is suitably encoded text output.

Version control tools, such as Subversion and Git, use lines of text as fundamental units. Hence, they work out of the box on LaTeX files to provide powerful support to collaborative editing and versioning. This goes well beyond the primitive capabilities of Word’s “track changes” function: authors can edit in parallel the same source file, inspect each other’s changes, and automatically merge individual variants into a master copy. Easy-to-read visual presentations of changes are still possible through a variety of graphical interfaces to version control software, or by means of other tools that work on text (try latexdiff for a presentation that looks like Word’s track changes).

Markup languages tend to enforce a clear separation between content and presentation. I wrote “tend to” because some markup languages do a better job than others at separating structural markup and presentation markup. LaTeX does not excel at this, since it does not always clearly distinguish between, say, an annotation that marks the beginning of a section (a structural detail) and one that marks a word to be displayed in a different font (a presentation detail). Nevertheless, writing documents in LaTeX lets you focus on content much better than WYSIWYG systems like Word, which are centered around commands to change presentation (font type and size, line spacing, page breaks, and so on) and offer limited or hard-to-use support to add complex structural information (section and subsection titles, cross references, and so on). In fact, I have the impression that only advanced Word users take advantage of functionalities such as to define styles and indexes. The situation in LaTeX is reversed: inexperienced users learn only very basic presentation-changing commands (such as to have text in bold and italic), but know well how to mark the beginning of sections, and how to introduce cross-references, bibliographic entries, and other structural information. Changing presentation details such as line spacing, font type, or the spacing of rows in tables is instead the domain of the LaTeX expert, who has hopefully also learned not to change them from the default, defined in a stylesheet, unless there is a compelling reason. In summary, markup languages help you focus on content, defer fixing presentation details to when the content is stable, and change presentation uniformly and robustly based on the intended structure of text.

Compared to intuitive WYSIWYG tools, using markup languages may slow you down: you may have to lookup the language’s syntax to do things you don’t know or remember from previous usage; and achieving the desired presentation form requires planning the organization of a document before starting writing, or however modifying it consistently at some point. But this kind of slowing down is a good thing: planning and paying attention to the structure beforehand is generally necessary to achieve a good document design.

Why TeX is better

To understand the unique strengths of TeX (and its companion Metafont) we should have an idea of its history, whose protagonist is the legendary computer scientist Don Knuth. Working on a new edition of his magnum opus “The art of computer programming”, he became strongly dissatisfied with the typographic quality achieved by state-of-the-art technologies, in particular when it came to typesetting mathematics. To solve the problem for good, he started designing the TeX system in 1977, expecting to finish the project during his sabbatical in 1978; he was off only by a little over 10 years. Knuth tells the story in his own words in this interesting interview (the linked segment is about how much time and fretting took him to devise a suitable scalable algorithmic definition of the shape for the letter “S”: I’m pretty sure he would disagree with the LaTeX vs. Word study regarding “the appearance of the text [being] secondary to the scientific merit of an article”).

As a result, TeX is a top-notch thorough solution to the problem of providing a typesetting system that offers very high-quality output on every machine where it runs. Almost 30 years since its first stable release, and with all its idiosyncrasies, TeX’s core remains technically unsurpassed and a de facto standard.

Several features of LaTeX derive from using TeX as back-end. An important one is the possibility of defining powerful macros — a feature LaTeX directly inherits from TeX (in fact, LaTeX is essentially an extensive collection of TeX macro). The possibility of having complete control on the back-end through macros provides great flexibility to LaTeX users, if at the expense of having to deal with an occasionally abstruse syntax.

Then: LaTeX?

If you care about typographic quality; if you think it is conducive to — not in contrast with — clarity of presentation and quality of ideas; if you’re willing to invest time now to become way more productive later; if you would like to take advantage of the outcome of decades of top-of-the-line tool development; and if you think microwaved TV dinners are a poor substitute for properly cooked food. Then, you may want to give LaTeX a serious try; or to start designing the next markup language that will replace it while remaining compatible with the TeX ecosystem.