1. trading places: Brent crude oil is traded in London commodity futures market, also known as ICE Brent crude oil futures. American crude oil is traded in the New York Mercantile Exchange, also known as NYMEX crude oil futures.

2. Subject matter: Brent crude oil is a mixture of four light and low sulfur crude oils produced in Beihai Oilfield, including British Brent crude oil and Norwegian Oslo crude oil. These crude oils are of good quality and widely traded. American crude oil is mainly Middle East light crude oil, such as Saudi Arabian light crude oil. Compared with Brent crude oil, American crude oil is less difficult, lower in cost and better in quality.