Simplify the following text for a Grade 11 native English-speaking person.
Original: The Prince of Wales Trophy , also known as the Wales Trophy , is an award presented by the National Hockey League ( NHL ) to the Eastern Conference ( formerly the Wales Conference ) playoff champions , prior to the final series of games for the Stanley Cup .
Simplified: The Prince of Wales Trophy , or simply the Wales Trophy , is a National Hockey League ( NHL ) trophy awarded to the Eastern Conference ( formerly the Wales Conference ) playoff champions . The trophy is awarded prior to the final series which are the championship games to decide the winner for the Stanley Cup against the Western Conference 's champions .