Online book on command-line Linux usage, and Gentoo Linux in particular
The book "Linux Sea" offers a gentle yet technical (from end-user perspective) introduction to the Linux operating system, using Gentoo Linux as the example Linux distribution. It does not nor will it ever talk about the history of the Linux kernel or Linux distributions or dive into details that are less interesting for Linux users. For various topics, the online Gentoo Handbook offers a very detailed approach and as such is mandatory reading for any Gentoo Linux user who wants to know the full power of this Operating System. Although there is definitely overlap between "Linux Sea" and the online Gentoo Handbook, "Linux Sea" is by no means meant to replace the online Gentoo Handbook. "Linux Sea" will attempt to focus on topics that everyday users would probably need to know to continue working with Gentoo Linux.