On April 30, music lovers celebrate International Jazz Day, a worldwide commemoration of the improvised, free-form music that started in the U.S. but has transcended borders and united people in all corners of the globe. Legendary pianist and composer Herbie Hancock is UNESCO’s goodwill ambassador helping to orchestrate the day’s events, highlighted by an all-star global concert in Havana.

Get ready by watching these artists explain why jazz, in the words of composer Jeremiah Abiah, is “the freest way to express life.”

And follow the festivities on Twitter @IntlJazzDay and with #JazzDay.