Recently, low-density parity-check (LDPC) codes have been adopted in Advanced Television Systems Committee 3.0 and 3rd Generation Partnership Project 5G standards. In this paper, we present their structures in detail. They are delicately designed, based on the structures of quasi-cyclic LDPC codes and multi-edge type LDPC codes. The differences in their base matrices and parity-check matrices used in both standards are highlighted from the viewpoint of the distinction between broadcasting and cellular communication systems. Numerical results show that they are very competitive in their respective areas.