Bash (Bourne-again shell) is the shell interpreter of the GNU project. Based on the Bourne shell (sh), Bash provides numerous improvements from the Korn shell (ksh) and csh. Bash is an open-source software distributed on the GNU GPL license. It is the default shell interpreter on many open-source Unix based systems such as GNU/Linux. It is also the default interpreter for Mac OS X and has been ported for Windows through the Cygwin project.
Warning: Despite being the main shell interpreter supported by Calcul Québec, it is never advisable to do computation with this language. Bash is a language that is meant to be a glue between other programs which do the computation. You should never, for example, use Bash to perform thousands of iterations of a loop.
To get more advanced information, visit this Advanced Bash-Scripting Guide.