= Store concepts =
When a user commits his changes into a [[Subversion]] repository, the changes are atomically applied to the tree stored in the repository. This produces a snapshot of the entire tree which can be referenced by its own unique id - revision number. But in fact, although each new [[Revision|revision]] may be represented as a separate tree, commit does not create c copy of the whole tree. Each revision is stored as delta against the previous revision.

{{attachment: revision1.pngp}}