The Money line is exactly the same as it is for every other sport. Pick the winner of the game and you win, regardless of margin of victory. For example, if you pick the San Jose Sharks to on the money line against the Los Angeles Kings, you would win as long as the sharks win. However, if they spread was as follows:
San Jose (-1.5); Los Angeles (+1.5)
If the San Jose Sharks won 3-2 over the Kings and you had picked the Sharks with the handicap, you would not win. Conversly, if you had picked the Los Angeles Kings, you would win because the Kings lost by 1 goal and had a +1.5 goal handicap.
The other major Hockey betting lines are Total Goals. This involves picking the Over/Under on the total goals in the game. If the Total Goals Line is set at 5.5 goals and you picked the under, you would win because the 2 teams combined for 5 goals in our example (3-2). This line ignores the final result of the game. This means that if you had picked the Under 5.5 goals, it makes no difference whether Los Angeles or San Jose won, as long as the two teams combined for 5 or fewer goals.
The smaller the line, the closer the game should be. The larger the betting line, the more likely the game is to be lopsided.
Below are the betting lines for the NHL. This includes Money Line (game winner) and over/under.