Version/source code control allows a team of software developers to efficiently share access to a common code-base. Version control systems allow users to check out source code, make changes and enhancements, merge their changes with the changes others have made (automatically in most cases), and check it back in to make their work visible to others. Version control systems tack each change (who made it, when, exactly what changed) and can roll back (undo) changes if something went wrong. Version control allows groups of source files to be tagged with an identifier (e.g. a release number) so those files can be easily retrieved in the future. ...and much more.
There are many popular version control systems; the system being used by the FIRST team is Subversion. Subversion uses a central repository model where source code is stored on a server and users download copies to their local machines to work on. Subversion is fully integrated with NetBeans? (and most other popular IDEs) so you don't need any new software to use it.
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