I am trying to install NVM as per these instructions
I typed in this command in terminal:
$ curl https://raw.github.com/creationix/nvm/master/instal
OSX 10.15.0 Catalina (released November 2019) changed the default shell to zsh.
The default shell was previously bash.
The installation command given on the nvm GitHub page needs to be tweaked to include "zsh" at the end.
curl https://raw.githubusercontent.com/creationix/nvm/master/install.sh | zsh
Note: you might need to ensure the .rc file for zsh is present beforehand:
touch ~/.zsrhrc