Billy has been actively developed since 1999. Billy 4.1 is launched 1-18-2004.
Billy 4 is the product of several separate research projects, all of which looked at discrete areas of artificial intelligence, and each of which have become a subsystem within Billy The notable subsystems within Billy 4 are:
- Natural Language Processing enables Billy to extract meaning from what you say
- Machine Learning and Natural Language Generation enables Billy to observe what you say and learn to produce his own free-form responses
- Conversation fingerprinting, allowing Billy to identify you just by talking to you
- Knowledge base and question answering allows Billy to learn facts from you within the conversation, and then answer questions about what he has learned
- Natural language math evaluation enables Billy to answer basic math questions
- Keyword-matching rules allow Billy, as a fallback, to use rules and scripts to produce responses
You can only use Billy if you download its program on your computer