A contour is a line that keeps the same height. Contour lines are drawn onto maps to show heights.

The brown lines on this river basin are contour lines.

Contour cropping is the method of planting and then harvesting where strips of land in hilly areas are planted alternately with different types of crop. It is designed to prevent soil erosion due to overland flow of water during storms.

Contour ploughing is the name for ploughing at a constant height across a hilly landscape. The pattern of the plough furrows forms wavy lines as it goes around the folds of valleys and around ridges. It is designed to prevent soil erosion during storms.