Adobe Acrobat produces PDF files that readers can use on any computer with the free Acrobat Reader software, and these files offer all the advantages of printed books: with Acrobat, we can now produce online documents whose visual design benefits from centuries of research and experimentation in book design.
For the first time, we can choose typefaces for online information that convey a specific "look and feel" and meet our legibility goals without worrying about whether our audience installed those typefaces on their computer. For the first time, we can combine white space, text, and illustrations to produce an attractive, readable document-- readable by people who don't own the software we used to create the file-- and without worrying that they'll resize the window and destroy the whole design. For the first time, we can produce documents that display on printers or computer monitors at the device's best resolution.
So if Acrobat's this great, where's the trouble? It lies in misunderstanding the software's purpose and inherent limitations.
There are two main reasons to use Acrobat: