This lecture covers the theory behind satellite localization, focusing on projections and transformations. The instructor explains the principles of map projections, the Swiss projection system, and the challenges of transitioning between different coordinate systems. The session also delves into the importance of understanding geodesy and cartography in GPS measurements, highlighting the impact of map distortions on distance calculations. Additionally, the lecture explores the concept of fixed points in geodetic surveys and the role of transformation services in coordinate calculations. Practical examples and demonstrations help students grasp the complexities of spatial data representation and analysis.