Concurrent Versions System or CVS for short has been and is currently the version control system of choice for both Drupal core and also for contributed Drupal modules. For discussion on the future of version control for the Drupal project see http://drupal.org/node/289117 - Why is Drupal still using CVS and how can I help change that?
Hello, I am Chris, a Drupal developer based in Lancashire, UK.