dash

Dash is a command line tool used in Unix-like operating systems, particularly Debian-based distributions like Ubuntu. It refers to the Debian Almquist shell, designed as a lightweight and efficient alternative to the more feature-rich bash shell.

Dash aims to be POSIX-compliant, following the standards set by the POSIX shell specification. It is intended for scripting purposes rather than interactive use, making it popular for system scripts and startup scripts where speed and efficiency are crucial.

Compared to bash, Dash has a smaller memory footprint and faster startup time, resulting in improved performance for scripts. It provides a simpler and more streamlined set of features, but lacks certain interactive functionalities found in more robust shells. Consequently, it may not be ideal for users who require complex scripting capabilities or advanced interactive features.