Ubuntu is a form of Linux. Most references on Linux will be applicable to Ubuntu, but each distribution of Linus has its own features, so if you are going to use a specific operating system (Ubuntu vs. Fedora, for example) you will be happier with a book about that distribution.
This is a selection of what I regard as the best books for the purpose, but if you are reading this post in late 2017 or later, and you click through to a particular book, do look around for more recent editions. Also, check out the book reviews on my other blog, which will include all sorts of science books, some politics, and a good number of computer related books.
For books on programming (in various languages, for kids and adults) check out this post.
Linux: General books
How Linux Works, 2nd Edition: What Every Superuser Should Know
Unlike some operating systems, Linux doesn’t try to hide the important bits from you—it gives you full control of your computer. But to truly master Linux, you need to understand its internals, like how the system boots, how networking works, and what the kernel actually does.
In this completely revised second edition of the perennial best seller How Linux Works, author Brian Ward makes the concepts behind Linux internals accessible to anyone curious about the inner workings of the operating system. Inside, you’ll find the kind of knowledge that normally comes from years of experience doing things the hard way. You’ll learn:
How Linux boots, from boot loaders to init implementations (systemd, Upstart, and System V)
How the kernel manages devices, device drivers, and processes
How networking, interfaces, firewalls, and servers work
How development tools work and relate to shared libraries
How to write effective shell scripts
You’ll also explore the kernel and examine key system tasks inside user space, including system calls, input and output, and filesystems. With its combination of background, theory, real-world examples, and patient explanations, How Linux Works will teach you what you need to know to solve pesky problems and take control of your operating system.
Yes, this is good: Linux For Dummies, 9th Edition
Eight previous top-selling editions of Linux For Dummies can’t be wrong. If you’ve been wanting to migrate to Linux, this book is the best way to get there. Written in easy-to-follow, everyday terms, Linux For Dummies 9th Edition gets you started by concentrating on two distributions of Linux that beginners love: the Ubuntu LiveCD distribution and the gOS Linux distribution, which comes pre-installed on Everex computers. The book also covers the full Fedora distribution.
Ubuntu Unleashed 2019 Edition: Covering 18.04, 18.10, 19.04 (13th Edition)
… unique and advanced information for everyone who wants to make the most of the Ubuntu Linux operating system. This new edition has been thoroughly updated by a long-time Ubuntu community leader to reflect the exciting new Ubuntu 16.04 LTS release with forthcoming online updates for 16.10, 17.04, and 17.10 when they are released.
Former Ubuntu Forum administrator Matthew Helmke covers all you need to know about Ubuntu 16.04 installation, configuration, productivity, multimedia, development, system administration, server operations, networking, virtualization, security, DevOps, and more—including intermediate-to-advanced techniques you won’t find in any other book.
Helmke presents up-to-the-minute introductions to Ubuntu’s key productivity and Web development tools, programming languages, hardware support, and more. You’ll find new or improved coverage of navigation via Unity Dash, wireless networking, VPNs, software repositories, new NoSQL database options, virtualization and cloud services, new programming languages and development tools, monitoring, troubleshooting, and more.
Other Linux Distributions
Not at all current, but of historical interest and probably available used: The Debian System: Concepts and Techniques and A Practical Guide to Fedora and Red Hat Enterprise Linux (7th Edition).
Using the Linux Command Line and bash shell
The Linux Command Line: A Complete Introduction
You’ve experienced the shiny, point-and-click surface of your Linux computer—now dive below and explore its depths with the power of the command line. The Linux Command Line takes you from your very first terminal keystrokes to writing full programs in Bash, the most popular Linux shell. Along the way you’ll learn the timeless skills handed down by generations of gray-bearded, mouse-shunning gurus: file navigation, environment configuration, command chaining, pattern matching with regular expressions, and more. In addition to that practical knowledge, author William Shotts reveals the philosophy behind these tools and the rich heritage that your desktop Linux machine has inherited from Unix supercomputers of yore. As you make your way through the book’s short, easily-digestible chapters, you’ll learn how to: Create and delete files, directories, and symlinks Administer your system, including networking, package installation, and process management Use standard input and output, redirection, and pipelines Edit files with Vi, the world’s most popular text editor Write shell scripts to automate common or boring tasks Slice and dice text files with cut, paste, grep, patch, and sed Once you overcome your initial “shell shock,” you’ll find that the command line is a natural and expressive way to communicate with your computer. Just don’t be surprised if your mouse starts to gather dust.
Linux Pocket Guide: Essential Commands
If you use Linux in your day-to-day work, this popular pocket guide is the perfect on-the-job reference. The third edition features new commands for processing image files and audio files, running and killing programs, reading and modifying the system clipboard, and manipulating PDF files, as well as other commands requested by readers. You’ll also find powerful command-line idioms you might not be familiar with, such as process substitution and piping into bash.
Linux Pocket Guide provides an organized learning path to help you gain mastery of the most useful and important commands. Whether you’re a novice who needs to get up to speed on Linux or an experienced user who wants a concise and functional reference, this guide provides quick answers.
Wicked Cool Shell Scripts, 2nd Edition: 101 Scripts for Linux, OS X, and UNIX Systems>
Shell scripts are an efficient way to interact with your machine and manage your files and system operations. With just a few lines of code, your computer will do exactly what you want it to do. But you can also use shell scripts for many other essential (and not-so-essential) tasks.
This second edition of Wicked Cool Shell Scripts offers a collection of useful, customizable, and fun shell scripts for solving common problems and personalizing your computing environment. Each chapter contains ready-to-use scripts and explanations of how they work, why you’d want to use them, and suggestions for changing and expanding them. You’ll find a mix of classic favorites, like a disk backup utility that keeps your files safe when your system crashes, a password manager, a weather tracker, and several games, as well as 23 brand-new scripts…