GIS 101

Tab/Accordion Items

A geographic information system (GIS) lets us visualize, question, analyze, and interpret data to understand relationships, patterns, and trends.* GIS help answer questions and solve problems using mainly maps but also involves globes, reports, figures, and charts. GIS are growing as education tools across disciplines – from science to history.

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AGOL is ArcGIS OnLine. ArcGIS is a type of GIS software for desktops; AGOL is the online version. We share AGOL maps and apps on this website. Using AGOL, we can share information quickly within our department as well as with our site users.

Think of a layer like a piece of wax paper with shapes drawn on it. Only these shapes (points, lines, or polygons) represent things like the North Pole, rivers, and state parks. Layers do not have much meaning by themselves.

Maps are layers with meaning; a map is one or more layers put in context. So, now, that piece of wax paper is laid upon an existing basemap – like one of North Carolina. You can have multiple layers on top of each other in a map. Depending on how they are laid out (i.e., which piece of wax paper is on top), you may not be able to see every part of every layer in a map. Because of this, you can toggle layers on and off when in a map.

Basemaps are maps that are used to give context. They are interchangeable and have different uses depending on your need. You have probably used basemaps already when relying on a GPS service; sites often allow you to change between three basemaps: cartoon streets; actual landscape imagery, and topographic displays.

Apps are the third piece of the puzzle. Using a map, you can create an app. An app is an interactive map - you can do more than turn layers on or off! For instance, you can measure distance between shapes in layers (ex., the distance from The North Pole to the Outer Banks); filter out shapes in layers (ex., only show state parks that have mountain biking trails); and calculate properties of shapes (ex., find the largest body of water in my county).