Why are PDFs so slow?

Not sure how to put this in technical terms, but why are PDFs so much more memory and CPU intensive than, say, Word files? On a slower computer, opening a PDF is big deal that requires you to make sure that minimal amounts of other processes are running just in case it crashes. Is it because of a lack of competition that has not provided Adobe any incentive to streamline PDfs? Acceptable (talk) 21:41, 6 December 2012 (UTC)

Acrobat is often horribly slow to start, at least in part because it's part of Adobe's attempt to build PDF into a sweeping document workflow nexus. PDF viewers that don't attempt to do anything but display PDFs (e.g. Okular) are often lighter. PDF is not itself an intrinsically inefficient or expensive format. 87.114.106.165 (talk) 21:59, 6 December 2012 (UTC)

I would say it is intrinsically inefficient & expensive… but as 87 says it's probably acroread itself that's the largest problem on your end. Evince is another even lighter alternative; more at list of PDF software. ¦ Reisio (talk) 22:54, 6 December 2012 (UTC)

I notice that most Adobe programs (Acrobat, Photoshop, Flash) tend to be resource hogs on Windows PCs. Even when running a PC with a powerful CPU and large amounts of memory, they can still cause problems. I wonder if Adobe is generally more favorable towards Mac computers? Because Photoshop runs seamlessly on it, especially compared to a Windows machine. 65.93.190.120 (talk) 23:08, 6 December 2012 (UTC)

Mac OS is based on Unix (for starters), and unsurprisingly less awful. ¦ Reisio (talk) 23:59, 6 December 2012 (UTC)

PDF supports lots of types of data, some of which are basically just like photographs of text (in the case of some scanned documents, this is rather obvious). If you had a hundred page document, and each page was a page-sized photo, you'd expect it to be darned slow, and it is. StuRat (talk) 07:12, 7 December 2012 (UTC)

Also, the whole original idea of a PDF was to let it embed fonts in the document, in order to let anyone get a perfect printout of your doc. Word documents don't do that, either. What we really need for a good answer, though, is an Adobe engineer to tell us a little about Acrobat Reader's performance. Tarcil (talk) 19:43, 8 December 2012 (UTC)

Animated GIF as wallpaper

Is there anyway to make an animated GIF function as a wallpaper in Windows 7 without losing the animation? I remember that it worked fine in Windows XP, but looking for answers on various forums seems to suggest that Windows disabled this function in Vista and 7, with the preinstalled wallpapers such as Dreamscene being the only animated wallpapers that will work. Are there any workarounds to this? 65.93.190.120 (talk) 23:03, 6 December 2012 (UTC)