The Levels of Islamic Unity

Countless blessings and congratulations be upon the believers all across the world and upon humanity in general, on the auspicious birth of the divinely appointed Messenger of Allah, the holy Prophet Muhammad (S) and Imam Sadiq (A).
So we've been celebrating Unity Week. And what a great week it was, commemorating the birth of the holy Prophet Muhammad (S).
But have you ever wondered, what are the levels of Islamic Unity?
Well, just to make your job a little easier, Sayyid Shahryar lists for us the different levels of Islamic Unity.
And Remember, "Stay United!".