Xiaomi, China's second-largest mobile vendor, recently announced that it made $188 million in just one day. Xiaomi accomplished this feat on a day known as Singles' Day, a China-observed holiday. Held on November 11 (that's 11/11, the first hint about why it's called Singles Day) was originally started in 1993 at Nanjing University and was celebrated only by male bachelors, hence the original name "Bachelors' Day."