The table lists the latest rate for each currency in the Federal Reserve's H.10 release, with the direction it is quoted in and the business day it applies to. The key facts at the top state the euro, the pound, the yen, the Canadian dollar and the Mexican peso in a sentence.
Reading the rates
The Federal Reserve quotes most currencies in units per U.S. dollar, so a yen rate of 150 means one dollar bought 150 yen. A few, marked with an asterisk in the release, are quoted in U.S. dollars per unit, so a euro rate of 1.10 means one euro was worth $1.10. The "Quoted as" column says which applies to each row.
When it updates
The Federal Reserve publishes the H.10 release weekly. This page reads it every few hours and updates at the same address after each release.