ELIZA's key method of operation (copied by chatbot designers ever since) involves the recognition of cue words or phrases in the input, and the output of corresponding pre-prepared or pre-programmed responses that can move the conversation forward in an apparently meaningful way (e.g. by responding to any input that contains the word 'MOTHER' with 'TELL ME MORE ABOUT YOUR FAMILY'). Thus an illusion of understanding is generated, even though the processing involved has been merely superficial. ELIZA showed that such an illusion is surprisingly easy to generate, because human judges are so ready to give the benefit of the doubt when conversational responses are capable of being interpreted as "intelligent".

Online chatbots save time and efforts by automating customer support. Gartner forecasts that by 2020, over 85% of customer interactions will be handled without a human. However, the opportunites provided by chatbot systems go far beyond giving responses to customers’ inquiries. They are also used for other business tasks, like collecting information about users, helping to organize meetings and reducing overhead costs. There is no wonder that size of the chatbot market is growing exponentially.

Disney invited fans of the movie to solve crimes with Lieutenant Judy Hopps, the tenacious, long-eared protagonist of the movie. Children could help Lt. Hopps investigate mysteries like those in the movie by interacting with the bot, which explored avenues of inquiry based on user input. Users can make suggestions for Lt. Hopps’ investigations, to which the chatbot would respond.

Die Herausforderung bei der Programmierung eines Chatbots liegt in der sinnvollen Zusammenstellung der Erkennungen. Präzise Erkennungen für spezielle Fragen werden dabei ergänzt durch globale Erkennungen, die sich nur auf ein Wort beziehen und als Fallback dienen können (der Bot erkennt grob das Thema, aber nicht die genaue Frage). Manche Chatbot-Programme unterstützen die Entwicklung dabei über Priorisierungsränge, die einzelnen Antworten zuzuordnen sind. Zur Programmierung eines Chatbots werden meist Entwicklungsumgebungen verwendet, die es erlauben, Fragen zu kategorisieren, Antworten zu priorisieren und Erkennungen zu verwalten[5][6]. Dabei lassen manche auch die Gestaltung eines Gesprächskontexts zu, der auf Erkennungen und möglichen Folgeerkennungen basiert („Möchten Sie mehr darüber erfahren?“). Ist die Wissensbasis aufgebaut, wird der Bot in möglichst vielen Trainingsgesprächen mit Nutzern der Zielgruppe optimiert[7]. Fehlerhafte Erkennungen, Erkennungslücken und fehlende Antworten lassen sich so erkennen[8]. Meist bietet die Entwicklungsumgebung Analysewerkzeuge, um die Gesprächsprotokolle effizient auswerten zu können[9]. Ein guter Chatbot erreicht auf diese Weise eine mittlere Erkennungsrate von mehr als 70 % der Fragen. Er wird damit von den meisten Nutzern als unterhaltsamer Gegenpart akzeptiert.

A bot is software that is designed to automate the kinds of tasks you would usually do on your own, like making a dinner reservation, adding an appointment to your calendar or fetching and displaying information. The increasingly common form of bots, chatbots, simulate conversation. They often live inside messaging apps — or are at least designed to look that way — and it should feel like you’re chatting back and forth as you would with a human.
Facebook has jumped fully on the conversational commerce bandwagon and is betting big that it can turn its popular Messenger app into a business messaging powerhouse. The company first integrated peer-to-peer payments into Messenger in 2015, and then launched a full chatbot API so businesses can create interactions for customers to occur within the Facebook Messenger app. You can order flowers from 1–800-Flowers, browse the latest fashion and make purchases from Spring, and order an Uber, all from within a Messenger chat.
At this year’s I/O, Google announced its own Facebook Messenger competitor called Allo. Apart from some neat features around privacy and self-expression, the really interesting part of Allo is @google, the app’s AI digital assistant. Google’s assistant is interesting because the company has about a decades-long head start in machine learning applied to search, so its likely that Allo’s chatbot will be very useful. In fact, you could see Allo becoming the primary interface for interacting with Google search over time. This interaction model would more closely resemble Larry Page’s long-term vision for search, which goes far beyond the clumsy search query + results page model of today:

For every question or instruction input to the conversational bot, there must exist a specific pattern in the database to provide a suitable response. Where there are several combinations of patterns available, and a hierarchical pattern is created. In these cases, algorithms are used to reduce the classifiers and generate a structure that is more manageable. This is the “reductionist” approach—or, in other words, to have a simplified solution, it reduces the problem.
“I’ve seen a lot of hyperbole around bots as the new apps, but I don’t know if I believe that,” said Prashant Sridharan, Twitter’s global director of developer relations. “I don’t think we’re going to see this mass exodus of people stopping building apps and going to build bots. I think they’re going to build bots in addition to the app that they have or the service they provide.”

Beyond users, bots must also please the messaging apps themselves. Take Facebook Messenger. Executives have confirmed that advertisements within Discover — their hub for finding new bots to engage with — will be the main way Messenger monetizes its 1.3 billion monthly active users. If standing out among the 100,000 other bots on the platform wasn't difficult enough, we can assume Messenger will only feature bots that don't detract people from the platform.

Note — If the plan is to build the sample conversations from the scratch, then one recommended way is to use an approach called interactive learning. We will not go into the details of the interactive learning here, but to put it in simple terms and as the name suggests, it is a user interface application that will prompt the user to input the user request and then the dialogue manager model will come up with its top choices for predicting the best next_action, prompting the user again to confirm on its priority of learned choices. The model uses this feedback to refine its predictions for next time (This is like a reinforcement learning technique wherein the model is rewarded for its correct predictions).
At a high level, a conversational bot can be divided into the bot functionality (the "brain") and a set of surrounding requirements (the "body"). The brain includes the domain-aware components, including the bot logic and ML capabilities. Other components are domain agnostic and address non-functional requirements such as CI/CD, quality assurance, and security.
The term "ChatterBot" was originally coined by Michael Mauldin (creator of the first Verbot, Julia) in 1994 to describe these conversational programs.[2] Today, most chatbots are accessed via virtual assistants such as Google Assistant and Amazon Alexa, via messaging apps such as Facebook Messenger or WeChat, or via individual organizations' apps and websites.[3][4] Chatbots can be classified into usage categories such as conversational commerce (e-commerce via chat), analytics, communication, customer support, design, developer tools, education, entertainment, finance, food, games, health, HR, marketing, news, personal, productivity, shopping, social, sports, travel and utilities.[5]