We have two different types of groups, those which are created and administered by the site (communities), and those created and run by our users (groups).
Our communities are full-blown niche social networks based on a common bond or interest. They are run and administered by affiliates with expertise and passion for their particular topic.
There are persona templates type that are optimally designed for those that wish to be active members in some particular communities. For example; there is a photographer or model persona type that are designed for photography groups.
Besides all their members, the communities and groups can contain blogs, polls, articles, wikis, discussion forums, community specific interactive shouts and photos surrounding a subject.
Anyone can create a group and there are different levels of visibility and security available.