Subversion a version control system, allowing retension old versions of files and directories (usually source code), log of who, when, and why changes occurred, etc.,
like CVS, RCS or SCCS. Subversion keeps a single copy of the master sources. This copy is called the source ``repository''; it contains all the information to permit extracting pre- vious versions of those files at any time.

For more information about the Subversion project, visit http://subversion.tigris.org. Documentation for Subversion and its tools, including detailed usage explanations of the svn, svnadmin, svnserve and svnlook programs, historical background, philosophical approaches and reasonings, etc., can be found at http://svnbook.red-bean.com/. Run `svn help' to access the built-in tool documentation. 


usage: svn  [options] [args]

Subversion command-line client, version 1.6.5.
Type 'svn help ' for help on a specific subcommand.
Type 'svn --version' to see the program version and RA modules
  or 'svn --version --quiet' to see just the version number.
Most subcommands take file and/or directory arguments, recursing on the directories.
If no arguments are supplied command, it recurses on the current directory (inclusive) by default. Available subcommands:
add
blame
praise, annotate, ann)
cat
changelist
checkout
cleanup
commit
copy
delete ( remove, rm)
diff
export
help
import
info
list
lock
log
merge
mergeinfo
mkdir
move (mv, rename, ren)
propdel
propedit
propget
proplist
propset
resolve
resolved
revert
status
switch
unlock
update
SubVersion.Apache.org