If youre a teacher and youre reading this I just want to say, good job and you should tell all of your students to subscribe. Another thing, on twitter people have .

Daphne Koller is enticing top universities to put their most intriguing courses online for free -- not just as a service, but as a way to research how people learn.

On any given day were lied to from 10 to 200 times, and the clues to detect those lie can be subtle and counter-intuitive. Pamela Meyer .

Finding the slope of a tangent line to a curve (the derivative). Introduction to Calculus. Watch the next lesson: .