45×90 points

Think of a map like a big piece of graph paper. Lines are drawn both vertically and horizontally to create little squares. Each square is called a point, and it helps us know where things are on the map. On one side of the map, the lines that go up and down are called longitude lines. On the other side, the lines that go side to side are called latitude lines. If you take the point where the 45th latitude line and the 90th longitude line cross, you get a special point called a 45x90 point. It's a way of telling people exactly where something is on the map.