Happy birthday to teen pop star Justin Bieber, who is celebrating his 18th birthday on Thursday (March 1).<br/> <br />A busy day is planned for the singer as a number of celebrations will be rolled out for the Canadian star.<br/> <br />Included in that is a group of dedicated fans or "Beliebers" will look to break a Guinness World Record for "Most Social Media Messages Within 24 Hours."<br/> <br />And in keeping with the birthday spirit, Hallmark has announced the release a series of Justin Bieber greeting cards that will debut April.<br/> <br />Fans will get the chance to see Bieber on "The Ellen DeGeneres Show" on Thursday (March 1) for what's being touted as a "spectacular celebration."<br/> <br />The singer will also make an appearance on Ryan Seacrest's radio show on his birthday. And not to be outdone, Madame Tussauds is unveiling another wax figure of the superstar.<br/> <br />Bieber was discovered in 2008 after posting videos on YouTube.<br/> <br />His debut album, "My World," followed in November 2009, and was soon certified platinum in the United States.<br/> <br />John Russell, Reuters
