Are all chatbots intelligent?

Chatbots are a dime a dozen these days and every bot claims to have AI. Everyone seems to have their own definition of AI. What does AI really mean in the context of chatbots and is that the same as machine learning? Traditionally in computer science literature, what we call chatbots today are referred to as "chatterbots". These chatterbots were one of the first problems tackled under the gambit of AI and popularised because of the Turing test.