# Markov chain: Show that states 0, . . N are essential and communicating with each other. What is the difference between essential and communicating?

Markov chain: Show that all states 0, 1, . . . , N are essential and communicating with each other. What is the difference between being essential and communicating in this case?

By the definition if i is essential, i → j implies i ← j.

But two states i and j that are accessible to each other are said to communicate (also concurrent), and we write i ←→ j .

What is the difference between essential and communicate? Thank you all!!!