What is Petrodollar?

[Daniel3]

Do you know what exactly is petrodollar? Well, I am not an expert on this subject but many years ago, the US signed a treaty with Saudi Arabia to protect their oil refinery if they only accept US Dollars as the currency to sell oil. Since oil was being sold for USD, oil became petrodollar. Interestingly, the treaty has ended now and there are no talks about renewing.