Bash (Bash) is the GNU Project's shell—the Bourne Again SHell. This is an sh-compatible shell that incorporates useful features from the Korn shell (ksh) and the C shell (csh). It is intended to conform to the IEEE POSIX P1003.2/ISO 9945.2 Shell and Tools standard. It offers functional improvements over sh for both programming and interactive use. In addition, most sh scripts can be run by Bash without modification.

The improvements offered by Bash include:

• command-line editing,
• unlimited size command history,
• job control,
• shell functions and aliases,
• indexed arrays of unlimited size,
• integer arithmetic in any base from two to sixty-four.

GNU Bash

ShellCheck
ShellCheck - Wiki

Shell Serie - Teil 1 - Verteilte Systeme in der Bash schreiben
Shell Serie - Teil 2 - Verteilte Systeme in der Bash schreiben
Shell Serie - Teil 3 - Skripte-TÜV: Ein Framework für automatisierte Tests
Shell Serie - Teil 4 - Komfortables Logging für die Bash
Shell Serie - Teil 5 - Kommandozeilenparser im Eigenbau
Shell Serie - Teil 6 - Mutexe und Semaphoren mit der Bash programmiert
Shell Serie - Teil 7 - Petri-Netze für Deadlock-freie Queues in der Bash

GNU Bash manual
Advanced Bash-Scripting Guide

Manual pages:

user@host:~$ man bash
user@host:~$ man bash-builtins

To install bash on Debian:

root@host:~$ apt-get -y install bash bash-completion

To check the status of :

root@host:~$