Saving library syntax

Hello, I have a unique problem. I do not always have access to the internet but I still want to program in my free time. A lot of the libraries I have do not give you a reference for the syntax and expect you to use their website to get it. My work around was to save the pages to my hard drive but for larger libraries, it becomes impractical and cumbersome. I was wondering if you guys ever save a copy of the syntax on your computer as a manual so you can reference it when you do not have a connection to the net? How do you do it?

The Arduino IDE comes with quite some manuals about the coding.
For most of the sensors I have a datasheet, not unimportant
Most libs com with examples that are quite instructive, otherwise I dive into the code of the lib itself.