What is the purpose of a key on a map?

Answer 1

The key explains what the map's symbols mean.

Answer 2

The key is the map's legend. It indicates what the various map elements and symbols represent.

Answer 3

so the reader knows what the symbols and colors mean on a map.

Answer 4

it is that a key or legned expaline the symbols used on the map

Answer 5

It tells you essential stuff - such as the scale of the map (1 inch to 1 mile etc). It also tells you what the little symbols mean (for example showing where hostels are)

Answer 6

Otherwise you might confuse a river with a road or you wont understand some of the symbols!