Grid references consist of a grid of squares on a map. Creating a grid reference is not so dissimilar from making a graph. Both involve numbers, an x-axis, and a y-axis. With grid references, the numbers on the y-axis are called northings, while the numbers on the x-axis are called eastings. As with x, y graph coordinates, the eastings coordinate comes first, and the northings number comes second.
Grid references are a solid way for people to find a spot on a map. Check out the attached image. Pretend that the star on the grid represents one of the best ice cream shops in a given city. People visiting that city might not know how to get there. The grid reference can help them figure it out. Now, these tourists know that this superb ice cream parlor is at 5, 2.
The grid reference could also be hypothetically utilized by countries at war. Pretend that the Country of Apple is at war with the Country of Pear. The Country of Pear’s commander has just spotted the Country of Apple’s troops. Now pretend that the star on the image represents where the Country of Apple’s troops are located. With the grid reference, the Country of Pear can identify their exact position and plan a strategy of attack accordingly.