The first diplomatic connection started between Cuba and Russia during the Cuban Revolution in 1959 when Fidel Castro managed to eliminate the dictatorship of Fulgencio Batista. During this period, Cuba received military and financial support from the Soviet Union. Cuba became one of the major allies of the Soviet and continued until the fall of the USSR. After the fall of the USSR, Cuba remained as Communist and maintain its foreign relation with Russia along with receive credits and close economic ties with each other.
Cuba has been a socialist state governed by the unique Communist Party since the sucess of the revolution leaded by Fidel Castro in 1959, which managed to remove the dictatorship of Fulgencio Batista.
After the collapse of the USSR (1991), Cuba lost its most powerful ally, that had helped them to survive after the trade embargo and the international sanctions that the US had set on Cuba. Therefore, the country experienced very severe economic consequences at this moment but this did not change the government or the economic system.
The Agricultural Revolution has therefore been cited as a cause of the Industrial Revolution. As enclosure deprived many of access to land or left farmers with plots too small and of poor quality, increasing numbers of workers had no choice but migrate to the city.
Answer: I personally remember things better by writing them down and listening because you activate another part of the brain when you write things down.