Unions
About unions
A union is a type of object representing many objects.
For example, a field with the type GeoJSONGeometry could be either a GeoJSONPoint, GeoJSONPolygon, or a GeoJSONMultiPolygon because they are all part of the union. Using a union instead of an object gives you flexibility.
GeoJSONGeometry
Represents any of the GeoJSON types.