Every day of your life is spent surrounded by mysteries that involve what appear to be rather ordinary human behaviors. What makes you happy? Where did your personality come from? Why do you have trouble controlling certain behaviors? Why do you behave differently as an adult than you did as an adolescent?Since the start of recorded history, and probably even before, people have been interested in answering questions about why we behave the way we do.

Language defines us as a species, placing humans head and shoulders above even the most proficient animal communicators. But it also beguiles us with its endless mysteries, allowing us to ponder why different languages emerged, why there isn't simply a single language, how languages change over time and whether that's good or bad, and how languages die out and become extinct.

How the Earth Works takes you on an astonishing journey through time and space. In 48 lectures, you will look at what went into making our planet - from the big bang, to the formation of the solar system, to the subsequent evolution of Earth.

Economic forces are everywhere around you. But that doesn't mean you need to passively accept whatever outcome those forces might press upon you. Instead, with these 12 fast-moving and crystal clear lectures, you can learn how to use a small handful of basic nuts-and-bolts principles to turn those same forces to your own advantage.

The power of an effective speech is undeniable. It has the capacity to engage, inform, motivate, and create change in an audience - and in the world. In this compelling 24-lesson course, How to Speak Effectively in Any Setting, taught by Molly Bishop Shadel, Professor of Law at the University of Virginia School of Law, learn the fine art of speaking clearly, effectively, and persuasively in contexts across the spectrum, from the board room to the bar room and everywhere in between.