What is the difference between a direct quotation of an exchange rate and an indirect quotation? If

Question:

What is the difference between a direct quotation of an exchange rate and an indirect quotation? If the exchange rate between the yen and the dollar changes from ¥80 = $1 to ¥90 = $1, has the yen appreciated or depreciated against the dollar? Has the dollar appreciated or depreciated against the yen?

Exchange Rate
The value of one currency for the purpose of conversion to another. Exchange Rate means on any day, for purposes of determining the Dollar Equivalent of any currency other than Dollars, the rate at which such currency may be exchanged into Dollars...