Recent Developments on the Internet: The common characteristic, which all these systems share, is that the approach is "bottom-up" rather than "top-down". This means that in these environments content and structure are not determined by professional, corp
M. Bos-Ciussi, and G. Rosner. Communities of Practice: Creating Learning Environments for Educators, 2, chapter 14, Information Age Publishing, Charlotte, NC, (2008)