[stfu]

Just to make the contrarian point:

I absolutely hate any format that is not a pdf file. It puts way too much limitation on the content. Just as an example: I use three "systems" most of the time, one windows, one ubuntu, one android tablet. Pdf works with each one out of the box, I can hight text or copy/past it, edit them, heck even open them in some graphic editing software and extract illustrations as vectors, save it in different formats. In contrast to that, for epub/mobi I don't even know what their native editing tool is so I can convert them into pdfs.

[davidw]

The problem with PDFs is that they make a lot of assumptions about layout and formatting, whereas mobi and epub are HTML based, and therefore work on a much larger array of devices - from mobile phones to Kindle for PC, including, critically, eInk based readers which are way better for sitting down to read than anything LCD based.

[nathanbarry]

Though if you are writing a book about design you often want the level of formatting and design ability that a PDF gives you. It's hard to give that up with an ePub.

[davidw]

If you need something to be pixel-precise, you'd probably just include a .png file.

eBooks aren't perfect for everything, though. I think a design book, for instance, is something I'd rather read as a paper book.

[whatusername]

If you haven't checked out Calibre for conversions then you should.

As others have said - the issue with PDF's is that they assume A4/Letter size. When you're reading on a smaller screen (especially a basic e-ink one) the content is much more important.

[kroger]

But a PDF doesn't have to be A4/Letter. I published a book recently (ebook in PDF, ePub and mobi and paperback) and decided to use 6.69 x 9.61 inches for the PDF. I found that this size looks good on paper and on screen.