The Singles Day, or Double 11, is a Chinese shopping holiday that originated as an unofficial holiday for bachelors. The date, November 11 (11/11), was chosen because the number "1" resembles an individual who is alone. The holiday has also become a popular date to celebrate relationships, with over 4,000 couples being married in Beijing on this date in 2011, compared to an average of 700 a day.

The holiday has become the largest offline and online shopping day in the world, with Alibaba shoppers exceeding 168.2 billion yuan (US$25.4 billion) in spending during the 2017 celebration. Rival JD.com hosts an eleven-day shopping festival as well, which garnered US$19.1 billion, bringing the Chinese total to US$44.5 billion.

The Singles' Day, or Bachelors' Day, originated at Nanjing University in 1993. Singles' Day celebrations spread to several other universities in Nanjing during the 1990s. November 11 (11/11), consisting of four "ones", was chosen as it represents four singles.

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