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We suggest opening another session of your Internet browser and loading an actual Geographic Data Viewer map. This way, as you go through the tutorial you can practice what is being explained.
 When you open a Geographic Data Viewer map through your Internet browser, you will see a new window that looks like the example you see here. At the top of the window, you will see the usual browser interface. As a rule, when an interactive map is open don't press any of the browser buttons on the Browser Interface! If you do, the link with Geographic Data Viewer servers may be severed. If this happens, simply close the map and re-open it.On the left, you can see the Toolbar. You will use the tools to look at, ask questions of, and change the map. The main window is the Geographic Data Viewer Map Window, where the map is displayed. On the far lower right is the Layer/Legend Panel where you control what is visible on the map. Above this is the Inset or Overview Map which gives the main map context by showing where it fits into the broader scheme of things. The area shown in the Map Window is shaded with a red box in the Overview Map. If you are feeling lost already... don't worry. Everything will be described in depth in the coming pages.
 With a Geographic Data Viewer map you can look at a specific area of interest. You can move around the map using the pan tool. The Pan tool lets you slide around to different parts of the map.Suppose you want to go north (up the map). Grab the Pan tool and grab (press and hold down the mouse button) onto the map and pull it down. Whatever part of the map you grab with the little hand will end up where you let go of the mouse button. Just like in real life. This works for moving any direction on the map.
The tool with the little plus sign lets you 'zoom in', while the one with the little minus sign lets you 'zoom out'. There are a couple of ways to use these tools. First, select one of them, go somewhere on the map and press the left mouse button. If it is the Zoom In tool the map zooms in. The center of the new map is wherever on the map you clicked the mouse button. The Zoom Out tool zooms out the same way. Second, you can zoom in more precisely by pressing the mouse button somewhere on the map, holding it down, and dragging a box. When you let go of the mouse button the new map extent will be the area defined by the box. When zooming out, the area defined by the box becomes the new map extent.
On a Geographic Data Viewer map, a maximum and minimum scale may be set. A maximum scale is set so you can't zoom in further than the data is designed to be used at. A minimum scale is so that people don't zoom out beyond where there is information. As well, some layers or labels for layers may only appear at certain scales. This is to improve the speed of the maps and to prevent them from getting cluttered at different scales. There are a couple of other handy buttons that will make life easier.
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The Zoom tools are unique to digital maps. They are very much like using an actual magnifying glass, as the icons imply. The main difference is you can't burn ants with them.
The first is the Previous Extent tool. This button jumps back to the previous map extent you were at. If you want to go back to where you were three zoom-ins ago, press it three times.
The other button is the Zoom to Full Extent button. It zooms you out to the maximum extent of the information.
The Zoom to Layer Extent button zooms to the maximum extent of the active layer. Next, you will find out how to make a layer active.For General Information 222-6800 • After Hours Emergencies 222-3070