systems, is that they support a clear distinction between copying and replication of data objects. Copying a u-form involves the creation of a new u-form (i.e., one with a different UUID), but with all attribute–value pairs identical to those of the original u-form. Replicating a u-form involves creating a new instance of the u-form with the same UUID as the original. Note that in a distributed system, two instances of the same u-form may be inconsistent (i.e., they may contain different attribute–value pairs). However, the fact that they have the same UUID means that they are intended to eventually be identical. History U-forms were developed at MAYA Design as part of the Visage Information Visualization System, a joint project of MAYA and Carnegie Mellon University funded by DARPA and The Army Research Laboratory. The name "u-form" derives from the term "e-form", a hypothetical "electronic form" proposed by Michael Dertouzos in his 1997 book "What Will Be". In addition to their continuing use in Visage, they have been used as the basis of a number of significant research and large-scale production systems, most notably the US Army's Command Post of the Future. References External links http://www.maya.com/portfolio/maya-universal-database http://www.bio-itworld.com/issues/2006/july-aug/infocommons/ http://www.asis.org/Bulletin/Jun-07/Bulletin_JunJul07.pdf http://www.biotech-online.com/fileadmin/artimg/the-universal-genetics-database_-information-sharing-in-genetics-and-beyond.pdf https://books.google.com/books?id=oDYEAAAAMBAJ&lpg=PA20&vq=u-form&pg=PA20#v=onepage&q&f=false Abstract data types Unique identifiers