The GNU Bourne-Again Shell
The GNU Bourne-Again SHell Table of Contents Bash is the GNU Project's Bourne Again SHell, a complete implementation of the IEEE POSIX and Open Group shell specification with interactive command line editing, job control on architectures that support it, csh-like features such as history substitution and brace expansion, and a slew of other features.
https://tiswww.case.edu/php/chet/bash/bashtop.html