Human, a documentary by French director Yann Arthus-Bertrand, features real stories of 2,020 people from 60 countries in 63 different languages. [Photo provided to China Daily]

Then, without a script, Arthus-Bertrand and his staff started their interviews.

"We didn't know how it (the project) would develop at the beginning. It was difficult for us to put the things together. But the biggest challenge was to reduce the original 10-hour version to a feature length," he says, smiling.

Financed by the Bettencourt Schueller Foundation, established by French tycoon Liliane Bettencourt to support cultural projects in 1987, the documentary now has several versions, including a 191-minute theater version and a three-part television version with each episode being 52 minutes long.

The documentary, which was premiered at the United Nations General Assembly in the presence of UN Secretary-General Ban Ki-Moon in September, can now be viewed by web users for free. Seven YouTube channels were created to distribute the film English, French, Russian, Spanish, Arabic, Italian and Portuguese.