The German Democratic Republic (GDR) (German: Deutsche Demokratische Republik, DDR), also known as East Germany, was the part of Germany that the Soviet Union occupied after World War II. The part of Germany that the western allies occupied was West Germany. East Germany was a communist dictatorship throughout the Cold War and the Democratic part of the name was hypocrisy. The USSR brutally suppressed an attempted uprising. The ordinary people had no freedom, were not allowed to emigrate, after the 1960's the Berlin Wall prevented most East Germans getting across. The STASI or secret police were widely feared.
About 1989 the collapse of communism in central Europe (and later other parts of the Eastern Bloc) started when the East German people defied their authorities, crossed the Berlin Wall and entered West Berlin en masse. There had been regular confrontations with the authorities in Leipzig shortly before.  West Germany and East Germany chose democratically to reunite after East Germany became an independent democratic nation. East Germany ceased to exist then though the part of united Germany that used to be East Germany was called former East Germany. For many years there were problems with poverty, also mass migration out of former East Germany and into former West Germany. The government of united Germany gave a high priority to building up the economy of former East Germany. The divide between the two parts of Germany will soon be history.
Of course, there were people who did not like being in East Germany. Two families escaped in a homemade hot-air balloon (read that again; yes it is true!).  However, not all East Germans were that smart. One guy found an idle plane and was actually flying deeper into the east before air traffic control in the West told him how to fly the plane.