Perhaps the most important aspect of implementing a chatbot is selecting the right natural language processing (NLP) engine. If the user interacts with the bot through voice, for example, then the chatbot requires a speech recognition engine. Business owners also have to decide whether they want structured or unstructured conversations. Chatbots built for structured conversations are highly scripted, which simplifies programming but restricts the kinds of things that the users can ask.
This kind of thinking has lead me to develop a bot where the focus is as a medium for content rather than a subsitute for intelligence. So users create content much as conventional author, (but with text stored in spreadsheets rather than anywhere else). Very little is expected from the bot in terms of human behavious such as “learning”, “empathy”, “memory” and character”. Does it work?
In 1950, Alan Turing's famous article "Computing Machinery and Intelligence" was published, which proposed what is now called the Turing test as a criterion of intelligence. This criterion depends on the ability of a computer program to impersonate a human in a real-time written conversation with a human judge, sufficiently well that the judge is unable to distinguish reliably—on the basis of the conversational content alone—between the program and a real human. The notoriety of Turing's proposed test stimulated great interest in Joseph Weizenbaum's program ELIZA, published in 1966, which seemed to be able to fool users into believing that they were conversing with a real human. However Weizenbaum himself did not claim that ELIZA was genuinely intelligent, and the Introduction to his paper presented it more as a debunking exercise:
ETL. The bot relies on information and knowledge extracted from the raw data by an ETL process in the backend. This data might be structured (SQL database), semi-structured (CRM system, FAQs), or unstructured (Word documents, PDFs, web logs). An ETL subsystem extracts the data on a fixed schedule. The content is transformed and enriched, then loaded into an intermediary data store, such as Cosmos DB or Azure Blob Storage.
These are one of the major tools applied in machine learning. They are brain-inspired processing tools that actually replicate how humans learn. And now that we’ve successfully replicated the way we learn, these systems are capable of taking that processing power to a level where even greater volumes of more complex data can be understood by the machine.
Some bots communicate with other users of Internet-based services, via instant messaging (IM), Internet Relay Chat (IRC), or another web interface such as Facebook Bots and Twitterbots. These chatterbots may allow people to ask questions in plain English and then formulate a proper response. These bots can often handle many tasks, including reporting weather, zip-code information, sports scores, converting currency or other units, etc.[citation needed] Others are used for entertainment, such as SmarterChild on AOL Instant Messenger and MSN Messenger.
Malicious chatbots are frequently used to fill chat rooms with spam and advertisements, by mimicking human behaviour and conversations or to entice people into revealing personal information, such as bank account numbers. They are commonly found on Yahoo! Messenger, Windows Live Messenger, AOL Instant Messenger and other instant messaging protocols. There has also been a published report of a chatbot used in a fake personal ad on a dating service's website.[44]

Context: When a NLU algorithm analyzes a sentence, it does not have the history of the user conversation. It means that if it receives the answer to a question it has just asked, it will not remember the question. For differentiating the phases during the chat conversation, it’s state should be stored. It can either be flags like “Ordering Pizza” or parameters like “Restaurant: ‘Dominos’”. With context, you can easily relate intents with no need to know what was the previous question.

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.
For example, say you want to purchase a pair of shoes online from Nordstrom. You would have to browse their site and look around until you find the pair you wanted. Then you would add the pair to your cart to go through the motions of checking out. But in the case Nordstrom had a conversational bot, you would simply tell the bot what you’re looking for and get an instant answer. You would be able to search within an interface that actually learns what you like, even when you can’t coherently articulate it. And in the not-so-distant future, we’ll even have similar experiences when we visit the retail stores.
A chatbot (also known as a spy, conversational bot, chatterbot, interactive agent, conversational interface, Conversational AI, talkbot or artificial spy entity) is a computer program or an artificial intelligence which conducts a conversation via auditory or textual methods.[1] Such programs are often designed to convincingly simulate how a human would behave as a conversational partner, thereby passing the Turing test. Chatbots are typically used in dialog systems for various practical purposes including customer service or information acquisition. Some chatbots use sophisticated natural language processing systems, but many simpler ones scan for keywords within the input, then pull a reply with the most matching keywords, or the most similar wording pattern, from a database.