It may be tempting to assume that users will navigate across dialogs, creating a dialog stack, and at some point will navigate back in the direction they came from, unstacking the dialogs one by one in a neat and orderly way. For example, the user will start at root dialog, invoke the new order dialog from there, and then invoke the product search dialog. Then the user will select a product and confirm, exiting the product search dialog, complete the order, exiting the new order dialog, and arrive back at the root dialog.

2. Flow-based: these work on user interaction with buttons and text. If you have used Matthew’s chatbot, that is a flow-based chatbot. The chatbot asks a question then offers options in the form of buttons (Matthew’s has a yes/no option). These are more limited, but you get the possibility of really driving down the conversation and making sure your users don’t stray off the path.
A chatbot (sometimes referred to as a chatterbot) is programming that simulates the conversation or "chatter" of a human being through text or voice interactions. Chatbot virtual assistants are increasingly being used to handle simple, look-up tasks in both business-to-consumer (B2C) and business-to-business (B2B) environments. The addition of chatbot assistants not only reduces overhead costs by making better use of support staff time, it also allows companies to provide a level of customer service during hours when live agents aren't available.
But, as any human knows, no question or statement in a conversation really has a limited number of potential responses. There is an infinite number of ways to combine the finite number of words in a human language to say something. Real conversation requires creativity, spontaneity, and inference. Right now, those traits are still the realm of humans alone. There is still a gamut of work to finish in order to make bots as person-centric as Rogerian therapists, but bots and their creators are getting closer every day.
Niki is a personal assistant that has been developed in India to perform an impressively wide variety of tasks, including booking taxis, buses, hotels, movies and events, paying utilities and recharging your phone, and even organizing laundry pickup and delivery. The application has proven to be a huge success across India and won the Deep Tech prize at the 2017 AWS Mobility Awards.
While AppleTV’s commerce capabilities are currently limited to purchasing media from iTunes, it seems likely that Siri’s capabilities would be extended to tvOS apps so app developers will be able to support voice commands from AppleTV directly within their apps. Imagine using voice commands to navigate through Netflix, browse the your Fancy shopping feed, or plan a trip using Tripadvisor on AppleTV — the potential for app developers will be significant if Apple extends its developer platform further into the home through AppleTV and Siri.
One pertinent field of AI research is natural language processing. Usually, weak AI fields employ specialized software or programming languages created specifically for the narrow function required. For example, A.L.I.C.E. uses a markup language called AIML, which is specific to its function as a conversational agent, and has since been adopted by various other developers of, so called, Alicebots. Nevertheless, A.L.I.C.E. is still purely based on pattern matching techniques without any reasoning capabilities, the same technique ELIZA was using back in 1966. This is not strong AI, which would require sapience and logical reasoning abilities.