View full lesson: http://ed.ted.com/lessons/what-does-it-mean-to-be-a-refugee-benedetta-berti-and-evelien-borgman About 60 million people around the globe have been forced to leave their homes to escape war, violence and persecution. The majority have become Internally Displaced Persons, meaning they fled their homes but are still in their own countries. Others, referred to as refugees, sought shelter outside their own country. But what does that term really mean? Benedetta Berti and Evelien Borgman explain. Lesson by Benedetta Berti and Evelien Borgman, animation by TED-Ed.

Your mobile phone, computer and game console have a bloody past — tied to tantalum mining, which funds the war in the Democratic Republic of the Congo. Drawing on his personal story, activist and refugee Bandi Mbubi gives a stirring call to action. (Filmed at TEDxExeter.) Talk by Bandi Mbubi.

Human beings have been campaigning against inequality and poverty for 3,000 years. But this journey is accelerating. Bono "embraces his inner nerd" and shares inspiring data that shows the end of poverty is in sight ... if we can harness the momentum. Talk by Bono.

View full lesson: http://ed.ted.com/lessons/jane-chen-a-warm-embrace-that-saves-lives In the developing world, access to incubators is limited by cost and distance, and millions of premature babies die each year. TED Fellow Jane Chen shows an invention that could keep millions of these infants warm -- a design that's safe, portable, low-cost and life-saving. Talk by Jane Chen.

When Nancy Lublin started texting teenagers to help with her social advocacy organization, what she found was shocking -- they started texting back about their own problems, from bullying to depression to abuse. So she's setting up a text-only crisis line, and the results might be even more important than she expected. Talk by Nancy Lublin.

View full lesson: http://ed.ted.com/lessons/fresh-water-scarcity-an-introduction-to-the-problem-christiana-z-peppard Fresh water is essential for life -- and there's not nearly enough of it for the world right now. Why is that, and what could we do? Christiana Z. Peppard lays out the big questions of our global water problem. And no, shorter showers are not the answer. Lesson by Christiana Z. Peppard, animation by Jeremy Collins.

In this engaging talk, world champion whistler Geert Chatrou performs the whimsical "Eleonora" by A. Honhoff, and his own "Fête de la Belle." In a fascinating interlude, he talks about what brought him to the craft. (Filmed at TEDxRotterdam .) Talk by Geert Chatrou.