The equator is 0 degrees, and the north pole is 90 degreees north latitude. The border between western Canada and the United States is exactly 49 degrees north latitude. For both latitude and longitude, every degree is broken down into 60 minutes. Each minute is further broken down into 60 seconds. Longitude and latitude measurements are located along side the grid measurements, but are printed in black.
Longitude is located at the top and bottom of the map.
The north south designation may be deleted from latitude if it is clearly understood that you are referring to the northern hemisphere. If there is any doubt add the N designation to prevent ending up somewhere in Chile. N. The grid system is generally much easier to use and is fairly standard for guide books and reference points used by guides, foresters, and land rescues. Most aircraft navigate with longitude and latitude and most gps units give coordinates as longitude and latitude. This makes it important to know both systems.