Watch some coverage of the People's Climate March that was timed to coincide with the UN Climate Summit in New York City. The march was attended by 400,000 people.

Geysers represent a very popular tourist attraction in Yellowstone Park. How do they work and where do they come from? And what is sandstone? The video answers these questions.

“Don't Answer Me” is a song by Alan Parsons and Eric Woolfson, the British duo behind the Alan Parsons Project. This is their first music video, which features an award-winning animation by Michael Kaluta, inspired by 1930s comic strips.

Lindsey Vonn describes her early days on the slopes, the encouragement she received from her father, and coming back from the many injuries she has endured on her way to becoming a champion skier. She also talks about her decision to compete against men in alpine skiing.

The song "Run" is from Irish band Snow Patrol's album "Final Straw." The video features frontman Gary Lightbody in a forest at nighttime.

In Yellowstone Park, visitors can see many indigenous animals in their natural habitat and wonder at the park's natural hot springs.

"China Girl" was originally co-written by David Bowie and Iggy Pop when they lived in Berlin. Although there are many interpretations of the song's meaning, the video particularly looks at and parodies Asian female stereotypes.

Natalie Fee concludes her Ted Talk with a few suggestions for what we can do to reduce how much single-use plastic we are sending into the earth's waterways.

Taylor Swift teams up with British singer Ed Sheeran and American rapper Future for this song "End Game," the video for which was shot in Miami, Tokyo, and London.

"One" and "ones" can replace nouns, but are not pronouns. They are prop words. Let's look at how they are used.

Why are some rock formations and animals found on more than one continent? The explanation dates back to the Ice Age.

Canadian singer Shawn Mendes released "Nervous" on his third studio album. It's a song about meeting a new potential love interest.

The Dropkick Murphys – an American Celtic band from Quincy, Massachusetts – level some heavy and hilarious criticism at Christmas and family members, but they are also having an awfully good time celebrating the holidays.

The birth cycle of kangaroos, affectionately called “roos,” is the subject of this video from National Geographic.

Why do some of the national parks in the United States resemble the European Alps? Geologist Dr. Robert Darga answers this question.