This tutorial uses the third party Homebrew package manager for macOS, which allows you to install packages from your terminal just as easily as you could on a Linux based system. You could use another package manager (or not use one at all), but Homebrew is highly reccomended.
If you have Homebrew installed skip the following command
To get homebrew, run the following command in a terminal: `/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)`