Xamarin.Forms.Maps what are "Degrees of Latitude" and how are they used in the context of the MapSpan class?

Question

I use Xamarin.Forms.Maps and there's something I don't understand. I'm using MapSpan and it's asking for degrees of latitude and longitude and I have no idea what they are. I looked online to try to understand but I got even more confused.

My question is, are these degrees, when added to the MapSpan constructor as such:

// the first 10 being the degree of latitude
// the second one the degree of longitude
MapSpan mapSpan = new MapSpan(position, 10, 10);

Does it mean that the map will have its Maps.VisibleRegion and display an amount of Pins to the equivalent of 10 degrees of lat and long, or 69 miles around the user ?

The thing that confuses me the most is that the Maps.VisibleRegion returns a LatitudeDegrees and a LongitudeDegrees, should it be used to figure out how many Pins to display to the user ? Or asked a different way, could these degrees load more pins outside of the user's screen because of the degree given ?