146 | 148 | An underlying design concept of the versioning model defined in openEHR is known as a "virtual version tree". The idea is simple in the abstract. Information is committed to a repository (such as an EHR) in lumps, each lump being the "data" of one Version. Each Version has its place within a version tree, which in turn is maintained inside a Versioned object (or "version container"). The virtual version tree concept means that any given Versioned object may have numerous copies in various systems, and that the creation of versions in each is done in such a way that all versions so created are in fact compatible with the "virtual" version tree resulting from the superimposition of the version trees of all copies. This is achieved using simple rules for version identification and is done to facilitate data sharing. Two very common scenarios are served by the virtual version tree concept: |