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.

Grammar! For many of us, the word triggers memories of finger-wagging schoolteachers, and of wrestling with the ambiguous and complicated rules of using formal language. But what is grammar? In fact, it's the integral basis of how we speak and write. As such, a refined awareness of grammar opens a world of possibilities for both your pleasure in the English language and your skill in using it, in both speech and the written word.

What can we still learn from C.S. Lewis? Find out in these 12 insightful lectures that cover the author's spiritual autobiography, novels, and his scholarly writings that reflect on pain and grief, love and friendship, prophecy and miracles, and education and mythology.

Jazz is a uniquely American art form, one of America's great contributions to not only musical culture, but world culture, with each generation of musicians applying new levels of creativity that take the music in unexpected directions that defy definition, category, and stagnation. Now you can learn the basics and history of this intoxicating genre in an eight-lecture series that is as free-flowing and original as the art form itself.

Between 1861 and 1865, the clash of the greatest armies the Western hemisphere had ever seen turned small towns, little-known streams, and obscure meadows in the American countryside into names we will always remember. In those great battles, those streams ran red with blood-and the United States was truly born.