If you're an avid YouTuber, you'll know that many popular song covers on the site are done a cappella, which means using only human voices.
The International A Cappella Festival has arrived in Hong Kong and will run until April 13. It's co-hosted by the Hong Kong Federation of Youth Groups (HKFYG) and the Hong Kong Jockey Club.
This festival, the fourth to be held here, features a cappella pros such as Australia's The Idea of North, Britain's Sons of Pitches, and the Hong Kong-based duo Robynn and Kendy. The artists will perform in different venues around the city.
"This is a good opportunity for people to deepen their appreciation for music," says Gabriel Lee, the festival's assistant programme manager. "By sharing a cappella through performances, we hope to inspire students to take it up."
And many students have been doing just that. In January, HKYFG launched its second A Cappella Leadership Training Programme. The programme annually selects 15 talented secondary school students to form an a cappella group that performs at the festival.
Songs on the students' set list included Avril Lavigne's Keep Holding On and Sammi Cheng Sau-man's rendition of Love for the Believer.
One of the students is Belilios Public School's Winky Wong, 16, who says a cappella is a great way for students to blow off steam from academic pressure.
"I can relax from my studies through singing a cappella, and I've also made lots of friends since it is a tightly knit group process," she says.
This year, the students performed last Friday and Saturday at the A Cappella Extravaganza at Queen Elizabeth Stadium. The event opened the festival with a bang, even though the second event, the A Cappella Marathon, was cancelled due to Sunday's rainy weather.
"It was exciting because more than 3,000 people watched us at the Extravaganza," says Winky's fellow group member, Mak Chun-ki, 17, of Queen's College.
"I was also very nervous because it was my first time facing so many people, but I signed up for this to challenge myself, and to make my parents proud. So it was all worth it."
Despite the encouraging turnout, Chun-ki still feels Hong Kong's music scene faces many problems.
"One problem is that lots of parents want their kids to study hard, so some of them don't support them in music, or they force their kids into it and make things more stressful. I am thankful my parents let me make my own choice to sing a cappella."
Although the students have finished taking part in the festival, the fun is yet to end. The Idea of North will perform at City Hall on April 10. The final show will be a free performance featuring several a cappella artists at Sha Tin Town Hall on April 13.
From now until April 11, you can even request performers to visit your school and hold a cappella workshops.
This weekend, local a cappella group, Hong Kong Melody Makers, will be collaborating with Hong Kong Youth Dance to bring audiences Magical Moment, a multimedia show.
And this show, perhaps, best illustrates the spirit of the festival. Lee says the show will even feature two wheelchair dancers.
"In Magical Moment, we want to highlight what people can do, rather than what they can't," he says.
"We want to show audiences that with the determination to go forward, one can succeed."