As the name suggests, Singles' Day began as a day for single people – apparently a chance to celebrate for the singletons, or "bare sticks", symbolized by the four ones in the date of 11 November – 11/11.
But in 2009, the online retail firm Alibaba adopted the day to promote a massive online shopping sale. It said the date was easy to remember, and conveniently placed in a consumer spending lull between National Day and Chinese New Year holiday.
Singles' Day rapidly became a hit. Other online retailers began cashing in, and Alibaba copyrighted the term "Double 11".
It says that since 2009, year-on-year sales of Alibaba growth has averaged 640%.
And with a total population of 1.3 billion people, there's still plenty of room for growth. But Alibaba also has global aspirations. It says more than 200 overseas merchants from more than 20 countries had confirmed participation in its Singles' Day sales this year, with multinational brands taking part in the "11.11 shopping festival" for the first time.
Even in China, however, Singles' Day has begun to draw some criticism.
Another user complained: "I don't know why people are so excited about the 'Double 11'. It's meaningless as they all hike prices before offering a discount."