It’s very easy to save a tutorial as a “web archive” file on any computer — Mac or PC. It’s like a perfect snapshot of a webpage, which you can read when you’re offline. A web archive file will preserve your tutorial purchase indefinitely, providing the full functionality of the live/online document.
When you open any web page, you are downloading not only the content, but a lot of other information about how the content should look and work. All of that stuff can be saved into a single file that can be opened and used later without an internet connection. A web archive file is basically just like any webpage, except that it is stored on your computer instead of the internet.
Note that “Web archive” is not a standard term, but more of a generic concept. The idea of a web archive has been called several different things on different computers and operating systems over the years. For instance, in Windows you don’t save a “web archive” file, you just “save a complete webpage.”
Here are specific saving instructions for the most popular web browsers. In all cases, opening the file again is as simple as double-clicking its icon.
A web archive file is pretty much useless without a computer. You can’t read a web archive file on an iPad or a Kindle, for instance (not without converting it into some other format first, anyway).
However, it is a perfect duplicate of the original tutorial. So anything you can do with the original, you can do with the archive … like saving it as a PDF.
For the slightly more technically inclined, Firefox needs a “plugin” to save webpages as a webarchive. Once installed, the option will be available, plus more advanced archiving options). Get it here, and follow the instructions to install it (pretty easy). Once you’ve got it, it works just like the others: