There is so much content in the world of "Star Trek" that there are bound to be mysteries that are never fully explained, and these 10 have kept us guessing.

In 1917, the government asked nearly every man in America the same question you're about to answer. Here's how the numbers ...

This video provides a concise overview of the multifaceted causes leading to the First World War, moving beyond the common ...

The Iran war plunged the global economy into one of the worst oil crises in history. Gasoline prices in the United States vaulted to a 4-year high. Some economists ratcheted up their odds of a U.S.