The Help and Support page of all our components includes a link to the detailed version history page(s) for the extension, so that you can see exactly what has changed since the version you are running. We do not support the idea of blindly updating software just because a new version is available, and for this reason we do not support the Joomla automatic updating mechanism. There is no need to install every update, but you should probably try to update everything every year or two as all the minor fixes and enhancements do tend to make the products easier to use.
Our versions follow the following convention:
XX is the major version number. This is incremented when the extension is substantially rewritten, or major new functionality is added, or upgrading to it requires some additional work on your part. When you upgrade an extension to a different major version, we recommend that you install it on a test site and check that the new version meets your requirements, before you install it on your live site. If you have customised the product css, you may have to re-implement your changes on the new version as the css class names and html structure may well have changed.
YY is the minor version number. This is incremented for most changes, including bug fixes, new functionality, and new language translations. You should be able to implement these straight onto your live site, although you should be in a position to reverse the install if necessary.
ZZ is the sub version. This is incremented for cosmetic fixes, language file updates, or minor fixes that don't affect important functions. These changes are not shown in our published version histories and you don't need to upgrade to them unless we advise you to.