The essential components of navigation are as follows:- being able to relate the map to your surroundings on the ground; knowing how to align (or orientate) the map with the ground; being able to interpret the contours on the map from a 2-D picture into a 3-D image in your head; measuring distances on the map and measuring the corresponding distance on the ground; using a compass to help orientate the map; and using a compass to walk on a bearing in a straight line between two points.