The is the command line shell. Commands can be issued via a terminal emulator.

Bash is an Sh sh-compatible shell that incorporates useful features from the Korn shell (Ksh ksh) and C shell (Csh 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.

Ash is a small inbuilt shell of Busybox.

Busybox is used when Puppy boots, it allows to keep the initial ramdisk small.

Busybox is a binary, that includes several commands, that else are only available as seperate programs.

But this small size has a price: not the full set of options of these programs are available.

So when Puppy booted, it additionally offers the bash, that is loaded from the big file pup_2xx.sfs.

Bash compatibility is required by several programs.

Shell Shells

Sh

Ash

AshCommands

Bash

BashCommands

BashQuickTips

BashDiff - Bash extended

BusyBox

GNU