Which of the following is the cardinal rule to read grid squares?

The cardinal rule for reading grid squares is to read right, then up. This method is essential for correctly identifying coordinates on a grid or map system, particularly in military navigation and planning.

When dealing with grid squares, the horizontal lines (often representing east-west directions) are read first from left to right. This directs you to the correct column of numbers that indicate the eastings. After identifying the correct column, you then read the vertical lines (representing north-south directions) from the bottom to the top, which gives you the northings. Combining these two readings provides a precise location within the grid square.

Understanding this sequence is critical in operational contexts, as it ensures accurate communication of positions and coordinates, which can be vital for mission success. This technique is not just arbitrary but a standardized method used in various navigation and mapping contexts, making it universally applicable and recognized within military operations.