Bash's full name is the GNU Bourne Again Shell. It is a programming language, specifically a shell scripting language, with an interpreter in a program named bash. It was created by Brian Fox of the Free Software Foundation, starting in 1989, and is now maintained by Chet Ramey. It is part of the GNU project for a free software operating system.
The bash program is used as a shell: either for entering commands as an interactive shell using a command line, batches of commands from a shell script, or a single command from an option.
In this book, we will refer to Bash as the software distribution and the programming language, and to bash as its interpreter program.
Bash is a Bourne-style shell, with some support for POSIX shell ...
