Original: The terms Eastern Bloc, Communist Bloc or Soviet Bloc were used to refer to the former Communist states of Eastern and Central Europe, including the countries of the Warsaw Pact, along with Yugoslavia and Albania,Eastern bloc, The American Heritage New Dictionary of Cultural Literacy, Third Edition.
Simplified: The term Eastern Bloc referred to the former Communist states of Eastern and Central Europe, including the countries of the Warsaw Pact, along with Yugoslavia and Albania, which were not aligned with the Soviet Union after 1948 and 1960 respectively.