what are isolines

Isolines are lines drawn on a map connecting data points of the same value. They are commonly used by geographers to represent different types of data, such as elevation, temperature, and atmospheric pressure. For example, contour lines are isolines that represent elevation on a map by connecting points of equal elevation. Isobars are isolines that show bands of high and low pressure and connect points that have the same atmospheric pressure. Isolines help the reader to recognize patterns and relationships between the geography of an area and data that might have been collected on the ground. They should have equal intervals between them numerically, and the scale used depends on the nature of the data being used and at which scale the map will tell the reader the most information.