Yash, yet another shell, is a POSIX-compliant command line shell written in C99 (ISO/IEC 9899:1999). Yash is intended to be the most POSIX - compliant shell in the world while supporting features for daily interactive and scripting use. Notable features are: - Global aliases - Arrays - Socket redirection, pipeline redirection, and process redirection - Brace expansion and extended globbing - Fractional numbers in arithmetic expansion - Prompt command and command-not-found handler - Command line completion with predefined completion scripts for more than 100 commands - Command line prediction based on command history