Facebook Inc has removed a restriction for users under 18 that previously limited who could see their online postings from photos to musings on the world-wide social network. The No.1 online social network said that teenagers would now be able to manually alter the settings and share information with public. Until now, a teenager’s postings on Facebook were only viewable to their friends, and to the friends of their friends. The change comes as Facebook faces increasing competition from a new crop of mobile and social services, such as SnapChat and WhatsApp, that have proven popular with younger users. Facebook said that it would show teenage users a special notice the first couple of times they attempt to post information to public, reminding the user that the post can be seen by anyone.