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Map projections generally use a rectangular grid coordinate system. These

grid coordinates are described in terms of easting and northing, the distances east
and north of an origin. The origin is assigned a set of coordinates and this is often
termed the false origin. Grid coordinates are usually expressed in units of metres.

MAP SYMBOLS (THE LEGEND)
Maps use symbols to represent features on the ground. These features
include roads, tracks, rivers, lakes, vegetation, fences, buildings, power lines etc.
Given the size of a map, it is not possible to show all features on the ground.

Large scale maps show more detail and a larger number of features. Depending on
the scale of the maps, features may have to be offset so they can be clearly shown
on the map, e.g. a roadway and a railway line may have to be separated
horizontally so they don’t overlay each other.

Colour plays an important part in symbols and some international
conventions apply to the use of colour. For example, blue for water features, black
for culture and green for vegetation.
Symbols are grouped in themes on the legend. While most symbols are

easily recognised as the features they represent, you can always refer to the map’s
legend.
What the map colors represent
White - most undeveloped areas lacking a tree cover (fields, parks, etc.);

Green - tree-covered areas (special patterns for orchards);
Blue - water features or marshes;
Red - major roadways;
Black - cultural features (schools, roads, railroads, place names);

Pink - urbanized areas (high concentrations of homes and buildings);
Brown - contour lines; used to show relief (changes in elevation);
Purple - used to show revisions in cultural features or changes in contours
after original map was made.

In order to make the topographic maps easier to interpret, symbols and colors
are used to represent various natural and man-made features. Some symbols are
designed to look like the feature when viewed from overhead. For example,
buildings are shown as solid objects in the shape of the building outline. Other

symbols are universally recognized representations such as a long line with small
cross marks to represent a railroad. Colors play an even more important role.
Rivers, lakes, and other bodies of water are shown in blue. Forests and heavily

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