and yet, http://citp.princeton.edu/memory/ , there's much work to be done on it. According to their findings, FileVault on OS X turned out to be the easiest to break.
Yes you can, the book will cover all the electronics stuff you will need to build the projects it presents. I find it to be a nice intro to physical computing stuff.
Tom Igoe, the author, co-wrote "Physical Computing" with Dan O'Sullivan, which is a book used in NYU's ITP for teaching artists and other non-engineers about electronics, microcontroller programming, mechanical devices, etc. So that should give you an idea of the expectations the book has from the reader, if you haven't done any electronics you will still enjoy it and, better yet, learn quite a bit from it.
I also suggest you check out his site http://tigoe.net/pcomp/ as it contains tutorials, syllabi from his classes at NYU's ITP, and other resources.