An AIML file contains Artificial Intelligence Markup Language (AIML), which is used to define the personality of a chat robot, or chatbot. It stores AIML, which is saved in XML format and is used to specify the heuristic conversation rules for a chatbot. AIML files can be created and edited by any plain text editor.

A chatbot is an AI program designed to perform auditory or textual conversations with a human. It may also be referred to as an interactive agent, talkbot, smartbot, or IM bot. Each chatbot typically has a collection of AIML files that guide its conversation pattern and give the robot "character." AIML was originally developed by Dr. Richard S. Wallace then shared with the free software community for further development between 1995 and 2002. It was first used by Artificial Linguistic Internet Computer Entity, more commonly known as A.L.I.C.E, which is a chatterbot developed to engage in conversation with humans. AIML has since been adopted by many other chatbot developers, such as Pandorabot and Verbot.