Debian Almquist Shell

dash (Debian Almquist Shell) is a POSIX compliant shell that is much smaller than bash. It can be usefully installed as /bin/sh (because it executes scripts somewhat faster than bash), or as the default super-user shell. Because it depends on fewer libraries, it is therefore less likely to be affected by an upgrade problem or a disk failure. It is also useful for checking whether a script uses only POSIX syntax. This shell was ported from NetBSD's ash.