What is the difference between a draft, unlisted and public?

A draft is unfinished, and only you can see it: it waits in Create → Drafts, and you can try it from the Studio without publishing. Deploying publishes it, and the visibility you pick decides who finds it. A companion set to Public appears in Explore, Browse and search. A companion set to Unlisted can be opened by anyone who has its link, but appears in no list. A companion set to Private is for you alone. You can change this whenever you like, and editing something you have already published is always free.