it is Nothing But Configuration management tool or Change
management tool Like VSS(Visual Source Safe).

Correct me if i wrong.
uday

Version control (also known as Revision control, source 
control) is the management of multiple revisions of the 
same unit of information usually the software. As software 
is designed, developed and deployed, it is extremely common 
for multiple versions of the same software to be deployed 
in different sites, and for the software's developers to be 
working simultaneously on updates. Bugs and other issues 
with software are often only present in certain versions 
(because of the fixing of some problems and the 
introduction of others as the program develops). Therefore, 
for the purposes of locating and fixing bugs, it is vitally 
important to be able to retrieve and run different versions 
of the software to determine in which version(s) the 
problem occurs. It may also be necessary to develop two 
versions of the software concurrently (for instance, where 
one version has bugs fixed, but no new features, while the 
other version is where new features are worked on). At the 
simplest level, developers could simply retain multiple 
copies of the different versions of the program, and number 
them appropriately. This simple approach has been used on 
many large software projects. While this method can work, 
it is inefficient as many near-identical copies of the 
program have to be maintained. This requires a lot of self-
discipline on the part of developers, and often leads to 
mistakes. Consequently, systems to automate some or all of 
the revision control process have been developed.