What is the definition of public here? Is public/private a matter of authentication, or authorization ? (e.g. trackable or paying) Or is it suppose to be "pri

What is the definition of public here? Is public/private a matter of authentication, or authorization ? (e.g. trackable or paying) Or is it suppose to be "private api is for internal use in a company" v. "public api is for external usage"? curl "https://joss-open-exchange-rates.p.mashape.com/latest.json" {"message":"Invalid Mashape key. If you are a Mashape user, get your key from your dashboard at https://www.mashape.com/login - To create a free Mashape account instead, go to https://www.mashape.com/signup"}