Internet Map Server - a Quick
ARC Internet Map Server (ArcIMS) is a program for displaying and
querying maps over the Internet. The maps are interactive - a user
can zoom in and out of maps, with different amounts of detail being
presented at different spatial scales. IMS allows different kinds
of map layers (roads, land use, water bodies) to be turned on or
off, so customized maps may be created. A user can also perform
interactive queries to collect information about different items
on the map. It is thus a fairly powerful way to distribute GIS data
over the Internet.
following primer covers the basics of using IMS - how to get and
retrieve information. In the few minutes it takes to read this,
you'll learn all you need to know to use our Coastal GIS Map Server.
to the IMS
on the link for a GIS map causes a lot of things to happen, it loads
all the appropriate data, and delivers the data over the Internet
to the web browser on your computer. As a result, some links are
slower than others, depending on the data being displayed. Remember,
in the old days, we had to wait for monks to draw out these maps,
and they took a really long time, so be patient!
figure shows the IMS display for the Minnesota Lake Superior Coastal
Boundary. The screen has four primary sections:
Toolbar for performs various map operations. You can hover over
the Toolbar elements in the figure below to obtain a description
of their functions - this feature works in the actual IMS session
Layers window on the right presents an interactive legend that
allows different map elements to be viewed and queried. The Visible
checkbox determines which layers are displayed. The Active
radio button determines which layer returns information when the
is used. Use
the Refresh Map button will redraw the screen to update
changes in the Layers window. The Toggle Tool in the upper
left corner of the toolbar will toggle between this Layers window
and a Legend window, which provides a color and symbol legend
for each of the map elements.
central map viewing frame diplays the visible layers. This map
can be manipulated (zoom, pan, query) using the Toolbar tools.
information window below the map returns results from map queries.
things to know:
layers composed of lines, such as roads and streams, overlay quite
easily. Layers which are based on polygons that cover the map, such
as land use or soil types, however, can only be viewed one at a
time. For this reason, a map layer may be 'hidden', i.e. the layer
might be turned on, but you won't be able to see it. By convention,
IMS draws layers at the bottom of the legend first. In the figure
above, the Land Use map is drawn first, followed by the Minnesota
Lake Superior Coastal Program layer. If a layer seems hidden, turn
off the layers above it to make it visible.
of the tasks you will perform in IMS involve setting up a view of
the map that shows what you want to see, and using the Identify
or query tools to retrieve information on map objects. The Identify
tool returns information in a data table that opens either in a
new browser window, or within the current map window. You can also
measure distance, construct sophisticated queries on tables, or
select and analyze multiple features. The best way to learn what
these tools do is to try them!
from the data display windows can be copied and pasted using standard
Windows/Mac copy and paste conventions.
that IMS stores information with a lot more precision than you really
need (or is justifiable, given the inherent error in the mapping
process). For example, the Identify tool might report the area of
one a feature as 27711.57356 square meters. Feel free to round this
to 27712 square meters. Heck, 2.8 hectares would be OK. (10,000
information on using IMS can be found at the ESRI web site under