grixit wrote: ↑Thu Dec 10, 2020 1:43 pm
At least it's not a pdf. I don't understand how that hateful format has become so ubiquitous.
/offtopic
So, as someone who edits and does some typesetting...
Largely for the reasons people hate them. I used to LOATHE them. I was, err. Wrong.
Everything has the disadvantages of its virtues and the virtues of its disadvantages and all. For print they're amazing; for web they're a Good-Enough Solution that's been declared the sweet spot between looking good, being useful, and being easy.
Essentially: they are relatively secure and extremely reliable in the hands of amateurs with unpredictable soft- and hard-ware, on both the production and the receiving ends, you can use them for both web and print without extra effort, and export to .pdf produces relatively small files.
I could set a lavishly illustrated book, export it to .pdf, and send it to 50 Quatloosians with different hardware, software and printers and each one of you would be able to either see it on-screen or print it, knowing you were getting the exact size, resolution, typefaces, and colour I intended, at a tiny filesize compared to the original InDesign (which you would need the software to read anyway) or uncompressed .tiff or .png.
HTML would be better. They would also take someone as long again as the print design did. There are various ebook formats that would be better, but they came along too late for one of them to grab .pdf's spot. And they're designed to be actively print-hostile, so you still need to create a .pdf.
Also, you can lock a .pdf and all its attributes, and even if you don't, Adobe has great version control and editing them leaves obvious traces. This is useful in any situation where there's a high potential for unauthorized or even malicious* editing, and it is AMAZINGLY useful for print work, as anyone who has ever spent an hour trying to verify colour separation over the phone or talk their printer through every single typeface in a document or sent a laboriously formatted .doc file to an OS or Linux user.
*sure, it's relatively trivial for someone in bad faith to fake up something that looks legitimate when printed. I've done it for legitimate reasons a lot: wrong size/ratio, typos, new info, no-you-can't-have-bleed, whatever.
What you can't do at all easily is alter the base file and not leave a trail.
And lastly, they work almost as well for screen readers as .epub or html, while jpg and .png and such aren't readable at all.
All of this is, of course, everything terrible about them too: you-the-end-user have to live with someone else's design choices, and it's annoying as Hell. You can't scroll, you can't reformat, you can't easily adjust the font size, or tweak the colours for your comfort, and if you find a mistake you are authorized to fix you probably have to reopen the original file, fix it there, re-export, and re-upload.
Online they are deeply annoying as compared to good web design. They are essentially print design forced into pixels, a quick-and-dirty way to get something up on your site without having to do a second layout from scratch.