You can read a nice introduction to various techniques used to design chatbots here: http://www.gamasutra.com/view/feature/6305/beyond_fa%C3%A7ade_pattern_matching_.php
Also, here are a few useful links:
- http://web.archive.org/web/20120320060043/
- http://ai-programming.com/bot_tutorial.htm
- http://www.alicebot.org/be.html
- http://en.wikipedia.org/wiki/List_of_chatterbots
- http://www.codeproject.com/Articles/36106/Chatbot-Tutorial
- http://www.slideshare.net/amyiris/ai-and-python-developing-a-conversational-interface-using-python
The Natural Language Toolkit (python) implements a few chatbots: http://nltk.github.com/api/nltk.chat.html
Simple pipeline architecture for a spoken dialogue system from the book Natural Language Processing with Python – Analyzing Text with the Natural Language Toolkit By Steven Bird, Ewan Klein, Edward Loper:
