What is the main difference between Google+ and Google Community. And what is the advantage of Google community whenever Google groups present..
Its absolutely similar to Facebook and Facebook groups. In Google+ profile when you share a post to circles, you can choose which kind of peoples want to see your posts. That can be control by you. In Google+ communities if you share something on that community you cant choose which kind of people want to see that post. Its limited public and seen by whole Community members. Google+ community sharing helps you to get more visitors to your content compare to Google+ post sharing on your profile.