How it works...

In this recipe, you learned how to add raster and vector data to a map. First, you opened an existing project that already contained a map with a single raster layer, this was the aerial color photograph. You then zoomed into that layer using a bookmark to examine it further. Bookmarks allow you to return to specific locations within a map by storing the extents and scale of your map view at the time you create the bookmark. This allows you to easily return to a specific location on the map. There is no limit on the number of bookmarks that are contained within a project. 

Once you zoomed into the location using the bookmark, you used the Explore tool to access information linked to a cell within the aerial photo to discover it included three bands. A different numeric value was assigned to the cell for each band, allowing the true color to be displayed in ArcGIS Pro. The information is presented in an HTML window that displays the attributes associated with the cell, feature, or features being identified. This functionality also allowed you to access the information from the parcels layer, which was a vector dataset. From this, you were able to see that vector and raster datasets can have different attributes that can be customized based on their purpose. 

In the recipe, you added a raster layer that represented the terrain or elevation. This came from the Esri Living Atlas as a web service which is hosted by Esri's ArcGIS Online. Rasters and vectors can both be published as web services. These are typically accessed through a REST point connection. REST stands for Representational state transfer. These types of connections provide interoperability across the web along with good performance. 

Finally, you added the parcels vector layer to your map and explored it. When you added it to your map, the parcel polygons were displayed in the map view. ArcGIS Pro does this by reading the x and y coordinates for each vertex that makes up the boundary of each parcel. This was demonstrated when you selected a parcel and displayed its vertices using the Vertices button on the Edit tab.   

These coordinates are typically stored in a real-world coordinate system that allows it to be displayed with other layers in the correct location on the Earth. The x and y coordinates for each vertex are referred to as a coordinate pair. Each pair describes a unique location. In the case of a polygon, no fewer than four coordinate pairs are required to fully describe the location and shape of a polygon. A line only requires a minimum of two, and a point only one. You will learn more about real-world coordinate systems later in this book. 

In addition to the spatial component of the parcels layer, you were able to view the associated attribute table. You saw how selecting features in the map also changed what records were selected in the attribute table, demonstrating the one-to-one relationship between features shown in the map and records listed in the attribute table.This showed you that vector data includes two components: spatial/geometry and attributes.

The link between the spatial features and the records in the table is automatically done within the data itself using the ObjectID or FeatureID (sometimes called FID) for each feature.