So if an orca attacking a shark is so rare, how do they usually behave? In this segment, we learn about how orcas around the world live and hunt.

Our friends at Numberphile provide a detailed look at how the game Connect Four is won or lost.

Why would a killer whale go after a great white shark? Enter Alisa Schulman-Janiger, a biologist who is very familiar with the different families of killer whales off the coast of California.

Orcas are at the top of the food chain, but it is unprecedented that they would go after a great white shark. From the boat, whale watchers and experts alike are shocked by what they see.

Prime Minister David Cameron will step down by October after the UK voted to leave the European Union. Mr. Cameron made the announcement in a statement outside Downing Street, in which he said he will attempt to "steady the ship" over the coming weeks and months, but that "fresh leadership" is needed.

David and Ben Crystal explain what goes into original pronunciation (OP) productions of Shakespeare and what they reveal about the history of the English language.

Here is a short animated video about the importance of fisheries for food security, health and growth in developing countries, highlighting the commitment of the EU to helping promote sustainable management of seafood resources and inclusive opportunities for trade and growth.

This video takes a look at hydrothermal vents and the novel life forms that thrive there in the absence of sunlight, fueled by underwater volcanoes. One of these harsh environments is the Axial Seamount off the West Coast of the United States.

Greentraveller's Richard Hammond shows you some of the loveliest and greenest spots in London, and gives some tips for navigating through the city.

When you listen to music, multiple areas of your brain become engaged and active. But when you actually play an instrument, that activity becomes more like a full-body brain workout. What's going on? Anita Collins explains the fireworks that go off in musicians' brains when they play, and examines some of the long-term positive effects of this mental workout.

Singer Meghan Trainor sits down with Ellen for her first interview since undergoing vocal cord surgery.

Jamila Lyiscott is a “tri-tongued orator;” in her powerful spoken-word essay “Broken English,” she celebrates — and challenges — the three distinct flavors of English she speaks with her friends, in the classroom and with her parents. As she explores the complicated history and present-day identity that each language represents, she unpacks what it means to be “articulate.”

The solar airplane Solar Impulse 2 was presented on April 9th, 2014. The construction of the experimental solar aircraft didn't happen in a day. Watch this video about the construction of Solar Impulse 2 and understand the steps that had to be taken to attempt the first solar flight around the world!

President Obama drops by a meeting with YouTube personalities to learn about how they're using YouTube to connect with an audience of millions of people and to discuss why it's important for young people to visit HealthCare.gov and learn more.

A film about the global sustainability work of The Prince's Charities, founded by HRH The Prince of Wales.