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.
[[http://puppylinux.org/wikka/BashDiff BashDiff - Bash extended]]
[[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.
Ash is a small inbuilt shell of busybox.
Busybox is used when Puppy boots, it allows to keep the initial ramdisk small.