Chatbots have been around since the 1960's. With the increased AI research in recent years as well as the advent of multiple virtual assistants, the Chatbots have come into the limelight again.
Chatbots can be developed on an individual level using various APIs, which is rather complicated and time-consuming. However, it awards the developer with in-depth customization. Sophisticated frameworks and platforms are also available to develop chatbots. They provide features like drag and drop modules. Some of the famous examples are: Chatfuel, Botsify, Flow XO, Beep Boop, Bottr, Motion.ai, IBM Watson