Gallery 3 was designed to provide the features that most users want, without being overburdened by providing all features to all users. To allow users with more specialized needs to have the features they really want, we've created a module API that lets you create and plug in your own modules. There are many modules available already for use. You can download and install them into your Gallery 3 to get great new functionality. Note that the contributed modules are not written by the Gallery team and we provide support on an as-is basis.
Modules are stored in our Git version control system on GitHub.