3D point cloud is a simple data structure representing both static and dynamic 3D objects. Though providing close-to-reality visualization, point clouds with high density raise massive demand for storage while sparse point clouds used for navigation require high precision. The emergency of compression technologies is mandatory in the form of standardization. A walkthrough for the technical approaches exploited in the two frameworks (V-PCC and G-PCC) under the MPEG standardization process is presented. Though with certain limitations, the achieved promising compression performances indicate a foreseeable evolution of the standard and a bright future for point cloud compression technologies.