Ursprünglich rein textbasiert, haben sich Chatbots durch immer stärker werdende Spracherkennung und Sprachsynthese weiterentwickelt und bieten neben reinen Textdialogen auch vollständig gesprochene Dialoge oder einen Mix aus beidem an. Zusätzlich können auch weitere Medien genutzt werden, beispielsweise Bilder und Videos. Gerade mit der starken Nutzung von mobilen Endgeräten (Smartphones, Wearables) wird diese Möglichkeit der Nutzung von Chatbots weiter zunehmen (Stand: Nov. 2016).[10] Mit fortschreitender Verbesserung sind Chatbots dabei nicht nur auf wenige eingegrenzte Themenbereiche (Wettervorhersage, Nachrichten usw.) begrenzt, sondern ermöglichen erweiterte Dialoge und Dienstleistungen für den Nutzer. Diese entwickeln sich so zu Intelligenten Persönlichen Assistenten.
Facebook Messenger chat bots are a way to communicate with the companies and services that you use directly through Messenger. The goal of chat bots is to minimize the time you would spend waiting on hold or sifting through automated phone menus. By using keywords and short phrases, you can get information and perform tasks all through the Messenger app. For example, you could use bots to purchase clothing, or check the weather by asking the bot questions. Bot selection is limited, but more are being added all the time. You can also interact with bots using the Facebook website.
Chatbots have come a long way since then. They are built on AI technologies, including deep learning, natural language processing and  machine learning algorithms, and require massive amounts of data. The more an end user interacts with the bot, the better voice recognition becomes at predicting what the appropriate response is when communicating with an end user.

Derived from “chat robot”, "chatbots" allow for highly engaging, conversational experiences, through voice and text, that can be customized and used on mobile devices, web browsers, and on popular chat platforms such as Facebook Messenger, or Slack. With the advent of deep learning technologies such as text-to-speech, automatic speech recognition, and natural language processing, chatbots that simulate human conversation and dialogue can now be found in call center and customer service workflows, DevOps management, and as personal assistants.

Multinational Naive Bayes is the classic algorithm for text classification and NLP. For an instance, let’s assume a set of sentences are given which are belonging to a particular class. With new input sentence, each word is counted for its occurrence and is accounted for its commonality and each class is assigned a score. The highest scored class is the most likely to be associated with the input sentence.
Dialogflow is a very robust platform for developing chatbots. One of the strongest reasons of using Dialogflow is its powerful Natural Language Understanding (NLU). You can build highly interactive chatbot as NLP of Dialogflow excels in intent classification and entity detection. It also offers integration with many chat platforms like Google Assistant, Facebook Messenger, Telegram,…
However, the revelations didn’t stop there. The researchers also learned that the bots had become remarkably sophisticated negotiators in a short period of time, with one bot even attempting to mislead a researcher by demonstrating interest in a particular item so it could gain crucial negotiating leverage at a later stage by willingly “sacrificing” the item in which it had feigned interest, indicating a remarkable level of premeditation and strategic “thinking.”
1. Define the goals. What should your chatbot do? Clearly indicate the list of functions your chatbot needs to perform. 2. Choose a channel to interact with your customers. Be where your clients prefer to communicate — your website, mobile app, Facebook Messenger, WhatsApp or other messaging platform. 3. Choose the way of creation. There are two of them: using readymade chat bot software or building a custom bot from scratch. 4. Create, customize and launch. Describe the algorithm of its actions, develop a database of answers and test the work of the chatbot. Double check everything before showing your creation to potential customers.
A very common request that we get is people want to practice conversation, said Duolingo's co-founder and CEO, Luis von Ahn. The company originally tried pairing up non-native speakers with native speakers for practice sessions, but according to von Ahn, "about three-quarters of the people we try it with are very embarrassed to speak in a foreign language with another person."
The classification score produced identifies the class with the highest term matches (accounting for commonality of words) but this has limitations. A score is not the same as a probability, a score tells us which intent is most like the sentence but not the likelihood of it being a match. Thus it is difficult to apply a threshold for which classification scores to accept or not. Having the highest score from this type of algorithm only provides a relative basis, it may still be an inherently weak classification. Also the algorithm doesn’t account for what a sentence is not, it only counts what it is like. You might say this approach doesn’t consider what makes a sentence not a given class.
I argued that it is super hard to scale a one-trick TODA into a general assistant that helps the user getting things done across multiple tasks. An intelligence assistant is arguably expected to hold an informal chit-chat with the user. It is this area where we are staring into perhaps the biggest challenge of AI. Observe how Samantha introduces herself to Joaquin Phoenix’s Ted in the clip below:
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.