CAST held a Congressional briefing on May 19, 2010 about the UDL Guidelines and the UDL Book Builder. The UDL Book Builder allows users to create books and has over 22,000 user accounts and nearly 24,000 books created, with over 1,400 books in the public library. The public library covers a diversity of topics that can be searched and includes books on history, animation, wars, music and more. The Book Builder also offers customizable coaches and supports for authors to help create materials.