In the terminology of Marx and Engels the words communism and socialism are synonymous. They are alternately applied without any distinction between them. The same was true for the practice of all Marxian groups and sects until 1917. The political parties of Marxism which considered the Communist Manifesto as the unalterable gospel of their doctrine called themselves socialist parties. The most influential and most numerous of these parties, the German party, adopted the name Social Democratic Party. In Italy, in France and in all other countries in which Marxian parties already played a role in political life before 1917, the term socialist likewise superseded the term communist. No Marxian ever ventured, before 1917, to distinguish between communism and socialism.
