We make take the names of players on the back of their NHL jerseys for granted. Let us have a bit of appreciation for these identification items because they were not always a standard part of the hockey unifrom. The numbering requirements of players on the professional ice started before the dawn of the NHL in one of its predecessors the National Hockey Association. This allowed fans to recognize their favorite skaters by their NHL jerseys and made the sport more personal to spectators just like it did in other sports. It also helped game officials to identify players for fouls, ice time and other amentities that afforded safe and fair game play via their NHL sweater numbers. Another perk of the player numbers allowed extra revenue for clubs as they could sell programs so that fans knew what numbers their players were.
This changed a bit in the 1977-78 season when the National Hockey League mandated that each player have a sweater nameplate sewn in right above their number on the back of the jersey. Many owners were incensed at the notion as that adornment would reduce the sales of programs. Famously the owner of the Toronto Maple Leafs, Harold Ballard, decided to ride the fine line of legality. Ballard not wanting to forfeit the program sales dollars obeyed the NHL and had the jersey nameplates placed on his Maple Leaf Sweaters, the only this is that he had them made to be the exact color and tone as the top portion of the jersey, with out a contrasting color to be found! From the distance that most fans were to the ice, the name plates could not be seen, so the spectators still needed the programs for player identification. This didn't last long though as the NHL soon revised the hockey nameplate mandate to include contrasting colors to the jersey and some key phrases on legibility from the stands.
