Since the news broke that Bernie Sanders, the independent senator from Vermont, would announce his bid for president on Thursday, many headlines have used one particular word to describe him. To cite just three of many examples: 

"Bernie Sanders: Socialist from Vermont set to announce campaign to be US President and challenge Hillary Clinton" — The Independent 

"A Socialist is Challenging Hillary" — The Daily Caller 

"Why Bernie Sanders, socialist senator from Vermont, will run for president as a Democrat" — Vox

Guess which piece, in the article body, comes closest to accurately identifying Sanders's political philosophy? Believe it or not, it's the Daily Caller, which describes him as "a self-proclaimed social democrat." (In its explainer, Vox didn't even bother explaining Sanders' socialism.) In reality, Sanders calls himself a “democratic socialist,” which is not quite  the same as being a social democrat.

As Sanders explained in a 2006 interview with Democracy Now!:

I think [democratic socialism] means the government has got to play a very important role in making sure that as a right of citizenship all of our people have healthcare; that as a right, all of our kids, regardless of income, have quality childcare, are able to go to college without going deeply into debt; that it means we do not allow large corporations and moneyed interests to destroy our environment; that we create a government in which it is not dominated by big money interest. I mean, to me, it means democracy, frankly. That’s all it means. 

But the Vermont senator himself is loose with his terminology, as he has praised the “long social-democratic tradition” of Nordic countries as examples of how the United States should operate as a nation. For instance, points to Finland's universal healthcare, free childcare, parental leave benefits, free higher education, low income inequality, and overwhelming unionization of workers. And sometimes he does indeed refer to himself, simply, as "a socialist."

So perhaps it's better to consider his policies themselves. Sanders wants a level playing field, where everyone born in America actually has the same opportunity for success, instead of "a government of the billionaires, by the billionaires and for the billionaires," as he puts it. He rails against the influence of the Koch brothers and other wealthy political donors and corporations on both Republicans on Democrats, ensuring that the rich stay rich and making sure the working class remain exactly that. While many Democrats claim to be in favor of leveling the playing field, few use the rhetoric Sanders does. He has suggested things like breaking up the largest banks and frequently refers to the United States as an oligarchy. 

Writing earlier this year on the "fear-mongering" over Sanders' politics, Penn Spectrum columnist Larry Liu noted the "confusion in America what socialism really is":

For starters, socialists don’t always agree among each other what the content of socialism is, but at the very least it contains the state control of the means of production, such as factories, offices, resources and firms. In the more advanced form of socialism, ownership is transferred to the workers. Bernie Sanders has sympathies for it as part of his 12-point proposal for the country, where he pushed for the opportunity for workers to set up worker-owned cooperatives (Sanders 2014). But it is questionable how far he will push it. When push comes to shove, he is a supporter of a social democratic Scandinavian-style welfare state in the form of better education, healthcare and social service provisions for the general population (Leibovich 2007) rather than the confiscation of companies from the private sector. 

America is partly a social democracy already, of course, thanks to programs such as Social Security, Medicare and Medicaid, unemployment insurance, and food stamps. Sanders doesn’t want the government to run the entire economy, but he does want the government to ensure that the economy doesn't regularly ruin millions of people's lives.