What are the different group types?

There are 4 types of groups: 

• Public: NRMN community members can join and participate.
  
  
• Private: Only accessible to those invited. Not searchable within Search Groups.
  

• Invite only: Shows in search, but can only be accessed by owners and members. Requires an invite request from members.
  
  
• Announcements: Members can subscribe to hear the latest news or broadcasting for a topic of interest. Any user can subscribe to announcements.