Bash is a commonly-used shell in many Linux distributions. Bash is a command interpreter. We can use bash to interact with the system. Bash is a command-line–only interface containing a handful of built-in commands; it has the ability to launch other programs and to control programs that have been launched from it (job control).
Bash is a default shell now. It is very convenient. For example, they remember commands that we have typed and let us reuse those commands. It also let us edit those commands, so they don’t have to be the same each time. And bash let us define our own command abbreviations, shortcuts, and other features.
Bash is programmable. We can write a bash script to handle our daily work. Whenever we find ourselves doing a task repeatedly, we should try to automate it by writing a shell script. There are more powerful scripting languages, like Perl, Python, and Ruby, but the Linux shell bash is a great place to start. After all, we already know how to type commands.
We will talk more about this later.