How To Write on PDF Online?
Easy-to-use PDF software
How can I write a multiple-pages document (A4) with HTML / CSS and save it as PDF?
While it may not be the kind of answer you're looking for, I'd argue that on a Mac, the easiest way is to open the HTML file in a web browser and choose to print it, then save it as PDF. On MacOS Yosemite. A very manual way, but very simple. I've worked with PDF on a few web projects, and there's a whole bunch of open source libraries for this purpose, in many languages—some are covered in the other answers. However, the question could use some details, such as if we're talking about applications or code libraries, manual or automation, bulk generation or not, and so on, as well as which platforms and devices we're targeting.
Write on PDF: All You Need to Know
If you have questions about your specific case, drop me an email (or tweet me).
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