What are some alternatives?
When comparing zsh and GNU Bourne Again SHell, you can also consider the following products
fish - The friendly interactive shell.
DASH - DASH is a secure, blockchain-based global financial network which offers private transactions.
Xiki - Xiki makes the command line friendlier and more powerful.
fshell - fshell is the Symbian equivalent of bash + telnet + a posix-like set of command-line tools.
win-bash - win-bash is a Windows port of the famous GNU bash (see GNU Bash homepage).
the xonsh shell - Xonsh is a Python-powered, cross-platform, Unix-gazing shell language and command prompt.