Is there a difference between Socialism and Communism?

Wikipeida defines Socialism as: “an economic system in which the means of production are publicly or commonly owned and controlled cooperatively, or a political philosophy advocating such a system”.

Wikipedeia defines Communism as: “ a sociopolitical movement that aims for a classless and stateless society structured upon common ownership of the means of production, free access to articles of consumption, and the end of wage labor and private property in the means of production and real estate.”

As a practical matter, Communist countries have been more totalitarian than European Socialist countries. But this may be the result of a small sample size rather than a fundamental difference.

In US politics, describing Obama as a Socialist is absolutely accepted by the GOP (and elicits little push back from the left). But calling him a Communist is viewed as “over the top”.

In Socialism and Communism the “means of production are publicly or commonly owned” (think US banks, Government Motors, NASA, public school, Midicare, Obamacare, Social Security, and flood insurance).

Private property in all these cases tends to be taken over by the state.
So is Obama a Socialist, a Communist, or neither?