U2 are the biggest Irish rock band ever and this one of their greatest hits. It's a song of earnest doubt and heartfelt yearning that reminds us that we are all human and all searching for some meaning in our lives.

English reggae and pop band UB40 were at the peak of their fame in the nineteen eighties, and they continue to make music and tour. They collaborated with new reggae band KIOKO for this single, which was featured on their album Bigga Baggariddim.

UNICEF Goodwill Ambassador Katy Perry delivers a special weather report on the devastating effects of climate change for the world’s children.

There is a lot of talk about how 3D printing could revolutionize the way that we make stuff. But what is 3D printing and how does 3D printing allow us to make almost anything from nothing? Professor Tim Minshall, Head of the Institute for Manufacturing at the University of Cambridge, explains it in this video, which is targeted at school-age students.

The University of Cambridge is one of England's greatest universities. There's no main campus – instead, the university's many colleges are scattered throughout the charming town center. Many colleges welcome the public to browse around.

Have you ever been unsure as to how elections work in the US on a federal and state level? This video explains it all.

Watch this video for "Dance The Night Away," the first top 20 hit of the American rock group Van Halen.

At the University of Sydney, physicist Derek Muller explores the possibility of an anti-gravity wheel through a series of field tests.

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

We meet a young woman, Caralie, on the street. She takes us to her apartment building. She checks her mail-box. She invites us inside and up the stairs to her third-floor apartment.

Caralie takes us into her kitchen. Here she talks about fruits, vegetables and preparing soup. She also shows us some important appliances in her kitchen.

Welshy Arms, a blues rock band from Cleveland, Ohio, have had their song "Legendary" featured in movies, on wrestling shows, TV shows, commercials, and even a video game soundtrack. But it started out on their album No Place Is Home.

White Lies are from England and make wonderful indie rock music. Check out this tune by them entitled “Farewell to the Fairground.”

The Graham Norton Show: Among the guests on Graham's sofa are Hollywood star Will Smith and musician Gary Barlow, who together with the audience perform the rap from The Fresh Prince of Bel-Air, the TV show that catapulted Will to stardom.

UK rock band Wizzard, with their charismatic big-bearded frontman and founder Roy Wood, scored their biggest hit ever with this glam rock Christmas classic from 1973. It is still played in the UK every Christmas season.