Introduction and historical review. Shape and size of the earth. Reference surfaces. Introduction to geodetic observations and methods. Geometry of the sphere and the ellipsoid (basic concepts, ρ, Ν,r). Geodetic coordinates (φ,λ). Arc length. Coordinate systems in two and three dimensions. Basic concepts and determination of reference systems: Astronomic, terrestrial, geodetic system. Topocentric and Geocentric systems. Determination of CGRS ’87. Introduction to map projections. Difference between topographic plane coordinates and projection plane coordinates. Basic computations in the plane and the sphere. Significant digits. Applications. Hatt and Mercator projection used in CGRS ’87. Reductions due to projection. Reference systems transformations. Transformation in the plane (x,y). Translation, rotation and scale. The course consists of field exercise with geodetic instruments (optical, digital, laser levels / tapes / optical squares, disto meters etc.).