From Sumerians and Babylonians we learned to use the sexagesimal system, based on number 60 (for instance, 1 hour = 60 minutes). They invented the first writing system, cuneiform writings on clay tablets to facilitate trade in Mesopotamia. They also invented beer, which facilitated mobilization of Sumerian laborers in public building projects. Subsequently, Egyptians imitated their methods in building the pyramids. Beer and bread were often ratioined. Both Chinese and Sumerians used the same sexagesimal time (24 hours, 60 minutes, etc.) This may have been due to their trade from ancient times. (Arabian horses were well known, and Babylonian language was the trade language in western Asia since the time of King Akhenaton.) The following tables eloquently testify their contributions to human civilization. Their descendants are modern Iraqis and Iranians.