Adding GIS data to a map using ArcMap

A map file in ArcMap (.mxd) holds layers of data. ArcGIS can import a wide variety of GIS data types, including shapefiles, layer files, rasters (images), and feature datasets. Often, GIS data obtained from public sources will already be in one of these formats. If you have data in tabular format, you will need to add XY data instead.

Start ArcMap, and select whether you want to insert data into an existing map or create a new blank map.

Tip: Before adding data to a map file, it is best to set reference data to be stored using relative paths instead of full paths. To do this, go to File > Map Properties... and click the Data Source Options... button at the bottom. Select Store relative path names and click OK. If the map and its data are moved to another location or another computer in the future, this setting will allow the data source mappings to remain intact, as long as the folder structure stays the same.

Click the Add Data button on the top toolbar to begin adding to your map. Browse to your map data and select it. To select multiple files, try holding down the Shift key or the Ctrl key while clicking. Once you have the desired selection, click OK.

Once data has been successfully added, it should be visible in the map area. If not, try zooming to the full extent . If ArcMap displays a message about being unable to determine the spatial reference of the data, you will need to assign a coordinate system to the data. Most data sources (such as the website where the data was obtained) will mention which system to use. Also, make sure that the imported layers are checked in the Table of Contents (left column). You can also try adjusting the symbology.