What is G0 and G1 in propagte in join IN CATIA V5?

In CATIA V5, G0 and G1 refer to the types of geometric constraints applied during the propagation of geometry in a join operation. G0 indicates a geometric constraint that enforces point continuity, ensuring that two curves or surfaces meet at a specific point without any gap. G1, on the other hand, represents tangential continuity, ensuring that the curves or surfaces not only meet but also share a common tangent direction at the joining point, resulting in a smoother transition. These constraints are essential for creating high-quality surface models in CATIA V5.