I've always been interested in AI and recently I've delved deeper into the workings of chatbots. I've looked at various examples such as Eliza, and how far they've come since then. But what are the various techniques that they now employ to build chatbots? I'm aware none as yet have properly passed the Turing Test so they're not quite perfect, but what algorithms do they use? What techniques? Thanks.

Ah that's interesting. I found an example of a Markov Chain where it takes in a load of text, and acquires root words and children words (words that come after the root word) and how often the children words come after the root words. Are there any other uses for Markov chains for Chatbots? Obviously it's only one part of the puzzle.