Sina Weibo
 Sina Weibo (NASDAQ: WB) is a Chinese microblogging (weibo) website. Akin to a hybrid of Twitter and Facebook it is one of the most popular sites in China in use by well over 30% of Internet users with a market penetration similar to the United States' Twitter. It was launched by SINA Corporation on 14 August 2009 and has 503 million registered users as of December 2012. About 100 million messages are posted each day on Sina Weibo.