Academia. At least, its widespread (almost universal) where I am studying. Mainly to manage citations, figures, and tables of contents automatically. Tools like Sharelatex are used for collaboration on papers.

We use a lot of LaTeX to make the midterms and final exams in the math department of my university. Everyone knows how to write in LaTeX, so if I make a internal helper package or a bunch of macros, then everyone can use it with minimal training.

The problem with wysiwyg word processors is that people get creative and it's very difficult to enforce the same style for all the material.

I use it for stuff more than a couple of pages long, because:

- I can use my text editor of choice

- I don't have to worry about messing with the formatting by accident

- It goes through git easily

Anything shorter and I just use a word processor, it's not worth the time messing with the boilerplate.

I do use it for writing letters - I have a template I just fill out and it spits out a nicely formatted letter with an envelope.

It's also handy for when I need documents in multiple languages - you can make one change to the formatting and it changes them all.

Laying out books. The fact that all of this can be done in a text file, without hidden codes and being tied to this file format or another, is extraordinary. Images are easily handled, fonts simply work (XeTeX & friends work well for me), and — with sufficient warnings — these files can be handed over to an author and edited without messing much, if anything, up. The PDFs generated work well with all the PDF tools I've attempted to use on them, and there's none of the weirdness that too-often shows up in Word or other WPs. If all you want is good-looking text, generated from truly basic documents, it will give it to you without effort.

LaTeX is particularly suited to print (and by extension PDF). When you get into writing your own custom LaTeX macros/commands, yes it's difficult. However, the vast majority of users are simply consuming these sorts of custom commands in the article, not producing them. This leads into environments where people writing papers or articles just use what's handed to them.

LaTeX works out amazingly for two very specific use cases: 1) Large, collaborative documents and 2) producing the exact same, highly structured print document over and over. I have pretty extensive experience with the second use case.

When I was Secretary for a non-profit organization, I had an entire little personal library of macros that sat on top of the minutes[1] package. I could open an empty text file, type in \attendee{Name} as people arrived. Type in \maketitle and do a quick preview and the document would instantly build out a front page that included if we had quorum or not, etc. I typed the document exactly as the meeting happened while marking up things like tasks (and who they're assigned to), decisions made (with voting tallies and who motioned what), and so on.

All that data would get duplicated to the end of the document in nice lists for quick reference. It had consistent formatting. The build system (a make file and latexmk iirc) would wrap my new file in the basic boilerplate and spit out the PDF for me to email. I consistently had the meeting minutes published an hour after every meeting whereas my predecessors often took 24 hours or more to publish meeting minutes due to Word being Word. Those documents also lacked a table of contents or the various appendices with summary data.

That said, there were things that I tended to avoid doing, like complex tables or something. There's something to be said for staying inside the box of what comes built into LaTeX. I recall giving up with floating an image to the left of a table on our title page and just plopping the image inline in a horizontally centered paragraph and then putting the rest of the title content beneath it.

Also, many documentation frameworks (sphinx comes to mind) use LaTeX under the covers to produce their PDF output. So you might think you're just using markdown or RST, but somewhere someone is converting that to LaTex or TeX in order to leverage a very good typesetting engine.

[1]: https://www.ctan.org/pkg/minutes

I'm a professor and research mathematician, and I use LaTeX for nearly everything I write. In addition to what others wrote --

- The way I conceptualize it, LaTeX is a word processor. So, for example, if I'm writing a rec letter and I choose LaTeX over Word, I'm thinking "I like this word processor better than that one."

- LaTeX/PDF is often criticized for being static, but in my experience, this is a good thing in most cases. If I am discussing the contents of a file with someone else, it is useful if we are both looking at exactly the same thing.

- I don't try to do any significant programming, or extensive customization of how my documents look. I agree that trying to do so would be annoying, but this is not part of my use case. If you look at a random selection of math papers, say here

https://arxiv.org/list/math/new

you'll notice that all of them look more or less identical.

PDF is unfortunately still the preferred format for sharing research papers.

And you're right, single file HTML with embedded images would be a much better format, but I assume publishers are preventing this.

> What is the intended use for LaTex these days?

Writing anything with complicated mathematical typesetting, for one; their have been improvements in word processors and thinks like MathML/MathJax, but they are still behind.

Works pretty well for autogenerated docs with more going on than is easy in Markdown, also - but that's often a bit of a wash.

Anything where decent typography is desired. Also, of course, mathematics. Mathjax is very good, but we sometimes want a canonical version of a document that looks the same for every reader, and doesn’t depend of the vagaries of constantly evolving browser engines. This means PDF.

I use it for puzzle books. Things like suduko, cryptograms, criss-cross, etc.

I have various custom C++ programs to generate the puzzles. But, getting the results to a formatted PDF was nearly impossible.

I use LaTeX as I can have my C++ program output a text file which, when compiled with LaTeX, creates the pretty puzzle books.

Essentially, I can press a button and “poof” I have a print-ready puzzle book ready to go up on Amazon.

My use case was for getting easy marks for proper APA formatting, which Zotero/EndNote and Mendeley don’t quite cover in one pass.

Word processor does not work with git and group collaboration and versioning properly.

HTML is not an authoring tool. Maybe pandoc or sphinx or other system would compete.

Master/PhD theses and papers in the sciences, particularly if formulas are involved.

Gold standard equation editing.