The Bourne-Again SHell (source code), almost always referred to simply as "Bash", interprets and executes input entered from a source such as the user or a program. Bash is an implementation of the shell concept and is often used during Python software development as part of a programmer's development environment.
Bash Guide for beginners is an entire book for those new to working with commandlines. It covers commands, paths, Bash shell scripting, variables and many other critical topics that are necessary to move from beginner to advanced Bash user.
Advancing in the Bash shell covers important concepts such as bang syntax, movement commands, tab completion and aliases.
Mastering Bash and Terminal shows methods for repeating commands, changing directories and handling background processes.
Ten Things I Wish I’d Known About Bash
covers some edge cases that are very useful to know about such as
proper exit code usage and configuration options through the set
command. There is also a great follow up post called
Ten MORE Things I Wish I'd Known About Bash
that covers new topics such as on-the-fly command re-execution using the
carrot character. The
Seven Surprising Bash Variables
post continues the series by examining built-in variables such as
PROMPT_COMMAND, CDPATH and REPLY which can simplify your
scripts by using values that Bash already has stored for you.
Google's Shell Style Guide covers how to write consistent, maintainable shell scripts, which is particularly important if you have ever tried to debug a hacky shell script that was never meant to be used by anyone other than the original author.
101 Bash Commands and Tips for Beginners to Experts is a well-done laundry list of tricks to explore.
Bash scripting quirks & safety tips
explains Bash basic programming constructs like for loops and variable
assignment then goes into ways to avoid weird issues in your code.
Safe ways to do things in bash shows you how to not shoot yourself in the foot by using safe coding practices with your shell scripts.
The Bash Infinity Framework source code provides boilerplate and a standard library for Bash projects so they are easier to read and maintain. If you have ever tried to read someone else's Bash scripts or even your own after setting them aside for a couple of months, you know that anything which makes readability better is a major step up from vanilla Bash.
Static status is a Bash application that generates a hostable, customizable status page for your services.
Replacing Bash scripts with Python
is a guide on using using Python for administrative scripting, including
what to do about replacing invaluable command line tools such as awk,
sed and grep.
Using Aliases to Speed Up Your Git Workflow has a bunch of shell aliases that make it easier for you to execute complicated or uncommon Git commands.
Creating a bash completion script is a great tutorial that walks you through a reasonably complex Bash script for completing syntax in other Bash shell scripts.
6 Tips Before You Write Your Next Bash Cronjob covers starting your scripts with shebang, redirecting output, timeouts and sudo privileges.
Better Bash history
shows how to make your Bash history more useful by having it store more
previous commands (which takes up more persistent storage but is not
a huge deal in 2019) and add timestamps to the history command.