Simplify the following text for a Grade 12 native English-speaking person.
Original: The company 's two principal divisions are the New York Mercantile Exchange and Commodity Exchange , Inc ( COMEX ) , once separately owned exchanges .
Simplified: The New York Mercantile Exchange ( NYMEX ) is the world 's largest physical commodity futures exchange , located in New York City . Its two principal divisions are the New York Mercantile Exchange and the New York Commodities Exchange ( COMEX ) which were once independent companies but are now merged .