In my search for a workable distinction, for the purposes of the simplest of conversations on sconomics or politics, this "summary" is a usefu, as a beginning to the quest. (My paragraphing)

"A summarized, simplified point of view" on the difference between Socialism and Communism

From the two above answers the second one is very thorough but it can be hard for a person who hasn't studied left-wing ideologies to understand it. Therefore I will try to simply explain how the difference between socialism and communism has changed throughout time, and the meaning of both terms has been contorted throughout history (Like Leninism being called Communism and Nazism being called Socialism).

In the dawn of all ideologies in the 19th century there were 5 main types of philosophies - Nationalism, Conservatism, Liberalism, Socialism and Utopian Socialism. After that many scientists and philosophers built on "Socialism" and many sub-ideologies were formed, one of them Communism. So you can imagine it this way - Socialism is the drive C on your computer and Communism, Libertarian Socialism, Marxism, etc. are the folders in the drive. When Marx and Engels came along, they started using Socialism and Communism interchangeably, but basically you don't see the word "communism" is used less in their text because, like all the other left-wingers of the 19th century, they were building on Socialism.

Then, when Lenin and the USSR came along they applied a industrialization-based economy to an agricultural country, therefore they failed and were at loss. Then they decided to create a "transition" to communism, which was surprisingly called socialism. So they claimed that they are a socialism country and socialism will lead to communism. Basically, their transition was a centralized capitalist system, and even Lenin admits that, because he thinks if Russia becomes a communist country it would be crushed through military force, and Stalin, in one of his secret letters claims that the USSR isn't socialist at all but if this went public it would mean the end of the USSR.

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