All of these conversational technologies employ natural-language-recognition capabilities to discern what the user is saying, and other sophisticated intelligence tools to determine what he or she truly needs to know. These technologies are beginning to use machine learning to learn from interactions and improve the resulting recommendations and responses.
The most widely used anti-bot technique is the use of CAPTCHA, which is a form of Turing test used to distinguish between a human user and a less-sophisticated AI-powered bot, by the use of graphically-encoded human-readable text. Examples of providers include Recaptcha, and commercial companies such as Minteye, Solve Media, and NuCaptcha. Captchas, however, are not foolproof in preventing bots as they can often be circumvented by computer character recognition, security holes, and even by outsourcing captcha solving to cheap laborers.
Chatbots succeed when a clear understanding of user intent drives development of both the chatbot logic and the end-user interaction. As part of your scoping process, define the intentions of potential users. What goals will they express in their input? For example, will users want to buy an airline ticket, figure out whether a medical procedure is covered by their insurance plan or determine whether they need to bring their computer in for repair? 

When you have a desperate need for a java fix with minimal human interaction and effort, this bot has you covered. According to a demo led by Gerri Martin-Flickinger, the coffee chain's chief technology officer, the bot even understands complex orders with special requests, like "double upside down macchiato half decaf with room and a splash of cream in a grande cup."
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.