I found this site which has a product comparison chart that might help:
https://support.garmin.com/en-CA/?faq=Arf40QDspf2OTMS8irl4t8
Some summary excerps from the site:
"Garmin offers two types of marine charts, BlueChart g3 and Garmin Navionics+ mapping. Both cartography charts provide a standard option and a Vision option."
"BlueChart g3 is an affordable option for compatible Garmin chartplotters. The product includes detailed navigation charts, tidal stations, currents, depth contours, IALA symbols, and detailed fishing (bathymetric) charts."
"BlueChart g3 Vision is a premium option that offers all of the same mapping and features as BlueChart g3, with extra features such as high-resolution relief shading for the continental US Coastline out to 40 miles, 3-D views, and aerial photos. This product is only compatible with certain chartplotters and sounders."
"Garmin Navionics+ and Garmin Navionics+ Vision is the most up-to-date cartography with daily downloads available. Integrated Garmin and Navionics content, it renders a whole new look and feel on the chartplotter with vibrant color palette and popular Navionics-style chart presentations and many other features."
I wasn't able to paste the comparison chart here so you'll have to go to the link for that.
Hope this helps.