The basic premise of Communism is that private property is eschewed for public ownership. By combining the resources of a whole community, each member of the community can benefit from the whole.
As an idea Communism can be traced back to ancient times. Its modern interpretation is most often attributed to Thomas More, who wrote a work of fiction called Utopia in 1516. In some ways Utopia was the birth of Science Fiction as a genre - in other ways it was the birth of a new social movement.
In 1848, Karl Marx and Friedrich Engels published The Communist Manifesto, which thereafter became the basis of communist parties that sprung up worldwide thereafter.
At its height, Communism was spread through many countries worldwide. In 2016, there are only 5 countries that are still communist: China, Laos, Cuba, North Korea, and Vietnam.