A CVS comparison is shown below. This shows all the
differences in a file since it was taken from the CVS repository. In
this case, in the local file a parameter was changed from "1" to "2".
A CVS comparison in Wolfram Workbench
After you have made changes to your code you can commit them to the
central repository. This brings up a dialog that lets you confirm what
you are doing and enter a description of your change.

The Workbench commit dialog
Once the commit has taken place, any user with access to the
repository can obtain your changes.