The European Market Infrastructure Regulation (EMIR) is a set of regulations produced within the European Parliament, European Commission and the European Securities and Markets Authority (ESMA) in response to the Global Financial Crisis
An exchange is a central platform for buyers and sellers to trade in specific products. All exchange trades are then sent automatically to a clearing house. Exchanges exist to trade equities, futures and bonds, in various forms of trading styles.
Generally short for 'credit exposure', meaning a positive or negative amount of money owed from one party to another. Having an exposure usually means the other party owes you money.