What is a PDF file, and how is it different from the print version?

PDF, or Portable Document Format, is an Adobe file specification for online documents. PDF files can be read with Adobe Acrobat, which is available for PC, Mac, Unix, PalmOS, Pocket PC, and other platforms.

Online versions of most of our titles feature color highlighting of code examples, and all feature a fully hyperlinked index and table of contents, internal hyperlinks where appropriate, and so on. Most print books are not in color. Due to differences in format, the page numbers of the PDF version will not coincide with page numbers in the printed edition (see below for an explanation).

How do I get my PDF?

You will be notified via email of the link to your PDF if your account allows for emails. Alternately, you can log into your account to see your link. Visit your account page. Click on the Your Bookshelf link in the sidebar to the right. You’ll find download links next to each title.

How do I check the status of my PDF?

If you visit your account page, you’ll see a list of all your PDFs. If a PDF has been updated since you last downloaded it, it’ll have an “Update me” banner. Click the link and we’ll send you the latest PDF.

If you don’t want to keep visiting our site to check your PDF status, subscribe to your personal RSS feed from your account page—we’ll send you an RSS notification whenever a PDF you own has changed.

What’s your update policy?

When you buy a PDF from us, you’re entitled to free updates for the lifetime of that edition of the book (if we create a new edition, then that will be a separate purchase).

Am I allowed to copy the PDF files?

You may make copies for you own personal use (e.g., one on your laptop while traveling and one on your home machine, backup copies in case your system crashes, etc.) but you may not give your PDF file to other people.

Are the PDF files restricted?

There is no copy protection or functionality restrictions in the PDF files. You may view or print them for personal use as you see fit.

You may not give your PDF, epub or mobi version to other people. The file you order is personalized with your name and other identifying information.

You can buy multiple licenses of a PDF file for your team or organization, in which case the PDF will be stamped with the number of allowed licenses. We’ll only send you one, so as to conserve everyone’s bandwidth.

Can I sell a used PDF like I can a paper book?

No; ownership of PDF, epub or mobi files cannot be transferred.

Can I print out the PDF files?

Yes, but the results may not be what you expect. The PDF files are formatted specifically for on-screen viewing, and as such have some differences from the paper book version.

The PDF versions show hyperlinks in color (some titles show code examples in color as well), which may or may not print out well depending on your printer.

The PDF pages are not set the same as in the book layout: left and right pages are set identically, which will make the margins turn out funny when printed. There are no blank pages, which means that some chapters may not open on the right-hand page when printed, as they would in the paper book version.