There are only textbook definitions of either. The world never works like textbooks imply, but communism is supposed to be a pure form of socialism, where private property does not exist. Socialism comes in degrees. For example, if all the hospitals in a country are owned by the state, you might say that country is socialist. This is opposed to pure capitalism, where all property is private.

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"Happiness lies not in the mere possession of money; it lies in the joy of achievement, in the thrill of creative effort. The joy and moral stimulation of work no longer must be forgotten in the mad chase of evanescent profits." FDR-First Inaugural Address