Intel actually bothered to copyright the mnemonics for the 8080 assembly language, so Zilog used the same binary instructions for its Z80 but different names at the assembly level. They had many more instructions, so having a different naming scheme (LD for a lot of stuff that were different names in the 8080) helped keep the complexity reasonable.

http://popolony2k.com.br/xtras/programming/asm/nemesis-lones...