The Sumerians were the first people to migrate to Mesopotamia, they created a great civilization. Beginning around 5,500 years ago, the Sumerians built cities along the rivers in Lower Mesopotamia, specialized, cooperated, and made many advances in technology. The wheel, plow, and writing (a system which we call cuneiform) are examples of their achievements.
1 In a presidential system, the legislature and the executive do not have to be aligned and often work against each other. 2  Policy implementation can be much slower and more moderated, at least in the US system.
A parliamentary system of government means that the executive branch of government has the direct or indirect support of the parliament.This support is usually shown by a vote of confidence. The relationship between the executive and the legislature in a parliamentary system is called responsible government. parliamentary system of government means that the executive branch of government has the direct or indirect support of the parliament.