In a parliamentary democracy the government is created out of and by the parliament. It is dependent on the support of the parliamentary party factions. The government, created by a majority coalition in the parliament, can also be deposed via a vote of Mißtrauen, mistrust. On the one side this gives the parliament a high degree of control over the government. On the other, however, the government can only govern by passing laws, which in turn requires strict discipline among the coalition parties in the parliament.
The presidential system is a different approach to democratic government. It‘s government – or administration, the executive branch of government – is elected directly by the people, and is therefore independent of the legislative branch, the Congress (Senate, House).
The United States is the most prominent example of the presidential system. There are also democratic forms of government which have aspects of both the parliamentary and presidential systems, such as France.
Germany is a classic parliamentary democracy. With one exception, federal elections have never produced a party with an absolute majority. Governments are always based on a coalition of two parties, who elect a chancellor to form a government. The chancellor then, in close negotiation with the coalition partners, chooses members for the cabinet. Traditionally these are the most powerful leaders of the coalition parties in the largest German states. They are power brokers in their own right and are considered to be capable of replacing the chancellor at any time.
Since all laws must be passed by a majority of the parliament, the government and its majority coalition in the parliament must work closely together. Any failure to pass a law is a clear signal of a possible break in the coalition.
Should the government, however, misuse its power over and against its colleagues in the parliament, the parliament can at any time dissolve the government via a vote of mistrust, which in turn leads to new elections. The government, should it not have the necessary support of parliament, has the same power to dissolve the parliament and force new elections.
In this sense, the chancellor‘s power is based on close cooperation not only with those cabinet members with their own independent political power base, but also with the influential factions in the parliament. The German chancellor is in the cabinet a primus inter pares, a first among equals.