The Bash had been the default shell on macOS for a long time. In the macOS Catalina, Apple replaced Bash with Z Shell (zsh), which is a more modern shell and compatible with Bash.

As an open source, community-driven framework to manage zsh configuration, Oh My Zsh makes it very easy for users to make the most of zsh. The Oh My Zsh framework contains a ton of plugins and themes, which would facilitate the use of zsh and make your shell look more professional. As the description on the official Github page, “Oh My Zsh will not make you a 10x developer…but you may feel like one.”

Z shell

After upgrading to macOS Catalina, the terminal will ask to change the default shell to zsh by:

chsh -s /bin/zsh

You can also change back to Bash:

chsh -s /bin/bash

Oh My Zsh


Install Oh My Zsh on macOS:

sh -c "$(curl -fsSL"

The configuration of Oh My Zsh can be edited in ~/.zshrc.


The Oh My Zsh themes are listed at and

An example of selecting theme:



The Oh My Zsh plugins are listed at and

An example of enabling plugins:



robbyrussell/oh-my-zsh - GitHub

Apple replaces bash with zsh as the default shell in macOS Catalina