The 11.11 Shopping Festival debuted in 2009 as a 24-hour online sale featuring a wide range of merchandise offered at 50% discounts. The promotion was originally created and hosted by Tmall.com, China’s largest B2C (business-to-consumer) shopping website, to raise awareness of online shopping among Chinese consumers while giving a sales boost to independent merchants selling on Tmall.

Nov. 11 was chosen for the sale because the date is easy to remember (11.11) and because it falls during an annual lull in consumer spending between the National Day and Chinese New Year holidays. Some refer to the shopping festival as the Singles Day Sale because it falls on Singles Day, a Chinese folk holiday likened to an anti-Valentines Day.

Just 27 Tmall.com merchants joined the event in 2009. In 2014 some 27,000 merchants and brands participated.