233 (èr sān sān) is a Internet “word” in China.It means “laughing”,just like “lol” or “:D”. It is from the No.233 emoticon of Mop forum which is one of the biggest forum in China and that emoticon is a laughing figure. And Chinese people on the Internet also use 23333 or 233333333333333 to express the happy emotion. The number of 3s you attach at the end is proportionate to how funny something is.