I didn't found anything in Wikipedia or on the Web (Maybe I don't know how to search). Chat is speaking with someone. But what is bot? Is it came from robot? Where the word robot came from?
A chatbot is a a computer program that simulates interactive human conversation, usually over the internet. The use of chatbots has increased with the introduction of artificial intelligence precepts.
Michael Maudlin invented the first chatbot program named Julia for Windows and the internet. Maudlin coined the term ChatterBot in the 1990s to describe these interactive conversation programs, a combination of the words chatter which means informal, superficial talk and bot, an abbreviation for robot.
Within a few years the term chatterbot was shortened to chatbot. Chatterbot and chatbot are portmanteaus, which are words that are formed by the melding of two unrelated words to create a new word. Synonyms for the terms chatbot and chatterbot are talkbot and Artificial Conversational Entity.
Chatbots are used as online assistants, toys and on social media platforms such as Snapchat. Increasingly, chatbots are used in social media to influence public opinion.