NetBSD's ash (Almquist sh) for Linux is a small (62K - no job control) Bourne-compatible shell. Great for machines with low memory, but does not provide all the extras of shells like bash, tcsh, and zsh. Most shell scripts are run compatible to bash. Note that most scripts written for Linux use some bash-specific syntax. The Slackware setup scripts are a notable exception, since ash is the shell used during installation.