Triple Alliance, a name given to several international agreements. The most important was a secret treaty that was signed by Germany, Austria-Hungary, and Italy in 1882 and remained in effect until 1915.
World War I, also known as the Great War, left Germany and other countries humiliated and angry. Germany viewed the armistice that ended World War I as a truce, rather than a surrender. This view was ignored. Learn about events that led to World War II. See more »
Dirigibleor Airship, a balloon that is self-propelled and that can be steered. There are three types: (1) the rigid dirigible, which holds its shape by means of a rigid metal framework around the gas cells; (2) the semirigid dirigible, which has a rigid keel along the bottom inside a single fabric gas bag, known as the envelope, but no framework around the envelope; and (3) the nonrigid dirigible, which holds its shape only by the pressure of the gas inside the fabric envelope. See more »