Bash (Bourne-Again SHell), is the default interactive user shell used in Ubuntu. Use this tag for questions specific to Bash, as opposed to generic POSIX shells.

Bash (the GNU Bourne Again SHell) is a Unix shell. It was built as a free replacement to the Bourne shell and includes many scripting features from other shells, such as csh and ksh. When called as sh, it is intended to conform to the POSIX 1003.1 standard. Bash features include:

  • Command line editing with the readline library
  • Command history
  • Job control
  • Functions & aliases
  • Arrays
  • Dynamic prompts
  • Integer arithmetic
  • Command (& filename) completion

Bash is the default interactive shell on most Linux distributions and is usually available on other Unix variants. Some GNU/Linux systems even use it as the default shell /bin/sh.

Because Bash is a common shell, you may be using it by default, so beware the temptation to choose this tag by default!

  • Use only if your question is about Bash-specific syntax or the interactive use of Bash.
  • Use the tag instead if your question is about sh (POSIX rather than Bash specific).
  • Use if you have a question about writing shell scripts (either POSIX or Bash specific).

Code Language (used for syntax highlighting): lang-bash