Referencing
Data to Real Locations
A GIS represents reality, it is not
reality. To be useful, a GIS map must accurately represent feature locations. To
determine the location of features in the real world or on a map, you need a reference
system—a set of lines of known location that can be used to determine the
locations of features that fall between the lines.
In a GIS, the reference systems used to
determine feature locations are called coordinate systems. In this session, you
will learn about different coordinate systems, how they work, and how to change
the coordinate system of a map. By understanding coordinate systems, you will
be able to manage your data in a way that increases the accuracy of your GIS maps and all the work you do with
them.