[Click on the images below to enlarge]
Black symbols are used for rock features (for example, boulders, cliffs and stony ground) and for linear features such as roads, paths and fences as well as for other man-made features (for example, ruins and buildings.
Brown symbols are used for landforms such as contour lines, small knolls, ditches & earthbanks.
Blue is used to mark water features: such as lakes, ponds, rivers, streams and marshes.
Yellow is to designate vegetation - specifically open or unforested land.
Green is used to show vegetation that slows down the passage of an orienteer. The darkest green areas, called "fight", are usually impassable.
White on an orienteering map signifies forest with little or no undergrowth - forest that an orienteer can run through.
Purple (or red) is used to mark the orienteering course on a map. Also, this colour is used to designate map corrections and out-of-bounds areas.