Projections? Coordinate Systems? PCS? GCS? Datums?... Ahhhh!!!

[BrianBaldwin]

I've always struggled to understand the relationships between datums, projections, coordinate systems, etc... nevermind trying to explain and teach these concepts to others! For me, the biggest issue was always reading through definitions and descriptions of these concepts and trying to build the mental image to understand how they related.

I was struggling to find a good diagram that explained the relationship, so I pieced the diagram below together (if someone has a better one... please post below!):

I also created a video walking through each of the components of the diagram. The video builds the diagram from the ground up and attempts to explain each (hence why the diagram looks so un-polished...):

If you have any thoughts, feedback, or better illustrations, please post them below! I'd love to hear how others are teaching these concepts (beyond just pulling apart an orange!).

Credits to Heather Smith for a few of her articles on these concepts:

• GCS vs. PCS: https://www.esri.com/arcgis-blog/products/arcgis-pro/mapping/gcs_vs_pcs/
• Coordinate systems: What's the Difference?: https://www.esri.com/arcgis-blog/products/arcgis-pro/mapping/coordinate-systems-difference/