WKT (Well-Known Text) is a plain text format used to represent vector data.
The Geography data type and its specific data types (GeoPoint, GeoLine, and GeoPolygon) can use the FromWkt method to load the vector data from a WKT representation.
Similarly, the ToWkt method allows you to obtain the vector data's representation in WKT format.
Note: The FromString and ToString methods are enabled for Geography data types only for compatibility reasons. Use
FromWkt and
ToWkt methods instead.
Geography data type
https://en.wikipedia.org/wiki/Well-known_text