Geodesy:
is the science of accurately measuring and understanding three fundamental properties of the Earth: its geometric shape, its orientation in space, and its gravity field— as well as the changes of these properties with time. [1]
National geodetic infrastructure:
is a system of technologies, techniques, facilities and services to address the sustainable development and application of Saudi Arabia National Spatial Reference System (SANSRS).
-----------------------------------------------------------------------------------------------------
[1]
NOAA. What is geodesy? National Ocean Service website,
https://oceanservice.noaa.gov/facts/geodesy.html , 11/05/20.