While I like the Mac GUI for about 3 decades now, I find myself doing more and more in the terminal. So I’ve become interested in shell scripting and this article has taught me a lot! This, together with Take Control of the Mac Command Line with Terminal for instance taught me what I should do about the bash profile when switching to zsh.

Later: there’s now an Apple technical note on this.

Even later: I found that, in contrast to bash, zsh does by default not allow comment signs (#) in interactive commands, so my .zshrc file now includes this line:
setopt interactive_comments # allow "#" as comment in interactive shell commands.