Couchsurfing founder Casey Fenton came up with the idea for the project in 1999 and launched the official website with co-founders Daniel Hoffer, Sebastien Le Tuan and Leonardo Silveira in 2004.

Couchsurfers get the chance to stay with locals and experience local culture first-hand, without having to spend on hotels or package tours.

In return, surfers write references for their hosts on their profile page, thanking them for their hospitality and vouching for them as reliable hosts.

Surfers can also write negative references for their host if they have an unpleasant experience.

Alternatively, couchsurfers can arrange meet-ups, say over a cup of coffee, to share about each other's cultures.

Couchsurfing has gained nine million members across 120,000 cities worldwide.

Singapore has about 34,000 members who have registered on the website.