There's a creepy transformation taking over our cities, says architecture critic Justin Davidson. From Houston, Texas to Guangzhou, China, shiny towers of concrete and steel covered with glass are cropping up like an invasive species. Rethink your city's anatomy as Davidson explains how the exteriors of building shape the urban experience -- and what we lose when architects stop using the full range of available materials.

When Michael Bierut was tapped to design a logo for public school libraries, he had no idea that he was embarking on a years-long passion project. In this often hilarious talk, he recalls his obsessive quest to bring energy, learning, art and graphics into these magical spaces where school librarians can inspire new generations of readers and thinkers.

Illness is universal -- but access to care is not. Physician Raj Panjabi has a bold vision to bring health care to everyone, everywhere. With the 2017 TED Prize, Panjabi is building the Community Health Academy, a global platform that aims to modernize how community health workers learn vital skills, creating jobs along the way.

We must face our fears if we want to get the most out of technology -- and we must conquer those fears if we want to get the best out of humanity, says Garry Kasparov. One of the greatest chess players in history, Kasparov lost a memorable match to IBM supercomputer Deep Blue in 1997. Now he shares his vision for a future where intelligent machines help us turn our grandest dreams into reality.