If you didn’t purchase this book from a reputable book seller or library, it has been stolen. Book piracy is a crime, and many times, when you download from a book piracy site, those files have been corrupted and will give you the worst case of computer syphilis ever. And if you’re not worried about your computer (or, you know, being a thief) those sites are also known for loading files with malware that can steal your passwords and banking information. Long-story-short: only read this book if downloaded legally—if not for me, then for the sake of your poor computer and all your innocent passwords. Thank you for your support and for helping to stop book pirates from ruining the industry for everyone.