Why did they make the Treaty of Versailles?

The Treaty of Versailles was designed to bring peace to Europe after World War I and to punish Germany for starting the conflict.
In very broad terms, the Treaty took land away from Germany, which was held solely responsible for starting the War; Alsace-Lorraine was given to France and the rich farmlands of Posen in Prussia awarded to Poland. The Treaty also put in place a number of measures to prevent Germany from starting another war. This involved severely limiting the size of Germany's armed forces. The German Army was to be restricted to 100,000 men, and the German navy reduced to just six battleships and no submarines.
Under the terms of the Treaty of Versailles, the German government was forced to pay compensation—or reparations, as they were called—for the enormous economic damage caused by the War. The total amount that the Germans would have to pay eventually came to 132 billion gold marks, a phenomenal sum that would wreak further damage on an already shattered economy.