Adding data to your map

Let's add a data layer to the US Counties map. Before we do, let's make sure ArcPro knows where your files are located. In the Catalog pane, expand Folders and see whether your data folder is shown.

If not, don't worry; your files are still where you left them! Right-click on Folders and select Add Folder Connection (don't see the Catalog pane? Click View|Catalog|Catalog Pane):

1. Browse to your folder and single-click it, then click OK (if you accidentally double-clicked, you will get a This container is empty message, and you will need to back up one level and single-click your folder):

Once you're connected to your folder, you're ready to add data to your map.

1. Click the Add Data button to add a data layer:

1.  The Add Data window will now appear. Browse to your newly connected folder:

All three of the files have the .shp extension. These are shapefiles. Shapefiles contain vector data commonly used in GIS software. Vector data is data where points (either single points on a map, or vertices) are represented by coordinates. Common vector features include points, lines, and polygons.

Although only one filename appears with a .shp extension, shapefiles are actually collections of related files. When viewed in File Explorer, you will see all of the related files (as seen in the following figure). ArcGIS treats all of these files as a single object. For this reason, it is helpful to work with files in Catalog, rather than File Explorer, so none of the pieces get lost:

Let's add the USstates layer to the US Counties map. We saw this layer when we clicked on the North America map, but we want to use it in the US Counties map, also.

1. Add the USstates.shp file: