According to the Journal of Medical Internet Research, "Chatbots are [...] increasingly used in particular for mental health applications, prevention and behavior change applications (such as smoking cessation or physical activity interventions).". They have been shown to serve as a cost-effective and accessible therapeutic agents for indications such as depression and anxiety. A conversational agent called Woebot has been shown to significantly reduce depression in young adults.
Malicious chatbots are frequently used to fill chat rooms with spam and advertisements, by mimicking human behavior and conversations or to entice people into revealing personal information, such as bank account numbers. They are commonly found on Yahoo! Messenger, Windows Live Messenger, AOL Instant Messenger and other instant messaging protocols. There has also been a published report of a chatbot used in a fake personal ad on a dating service's website.
Efforts by servers hosting websites to counteract bots vary. Servers may choose to outline rules on the behaviour of internet bots by implementing a robots.txt file: this file is simply text stating the rules governing a bot's behaviour on that server. Any bot that does not follow these rules when interacting with (or 'spidering') any server should, in theory, be denied access to, or removed from, the affected website. If the only rule implementation by a server is a posted text file with no associated program/software/app, then adhering to those rules is entirely voluntary – in reality there is no way to enforce those rules, or even to ensure that a bot's creator or implementer acknowledges, or even reads, the robots.txt file contents. Some bots are "good" – e.g. search engine spiders – while others can be used to launch malicious and harsh attacks, most notably, in political campaigns.
A representative example of a chat bot is A.L.I.C.E., brought to artificial life in 1995 by Richard Wallace. The A.L.I.C.E. bot participated in numerous competitions related to natural language processing evaluation and obtained many honors and awards, and it is also worth mentioning that this chat bot won the Loebner Prize contest at least three times, it was also part of the top 10 at Chatterbox competition, and won the best character/personality chat bot contest.
Chat bot, chatbot or chatterbot, can be found on screens and in the virtual worlds, but also in the real world, for example holographically projected or as physical talking and responding puppet, toy or robot. Often, chat bot appears online and in instant messenger programs such as Windows Live Messenger, AOL Instant Messenger or Google Talk, where a chat bot is part of the buddy, contact or follow list of the human user. Chat bot appears on many other platforms as well, such as social networks (e.g. Facebook), virtual worlds (e.g. Second Life) or mobile devices (e.g. iPhone).
Despite the fact that ALICE relies on such an old codebase, the bot offers users a remarkably accurate conversational experience. Of course, no bot is perfect, especially one that’s old enough to legally drink in the U.S. if only it had a physical form. ALICE, like many contemporary bots, struggles with the nuances of some questions and returns a mixture of inadvertently postmodern answers and statements that suggest ALICE has greater self-awareness for which we might give the agent credit.
The classic historic early chatbots are ELIZA (1966) and PARRY (1972). More recent notable programs include A.L.I.C.E., Jabberwacky and D.U.D.E (Agence Nationale de la Recherche and CNRS 2006). While ELIZA and PARRY were used exclusively to simulate typed conversation, many chatbots now include functional features such as games and web searching abilities. In 1984, a book called The Policeman's Beard is Half Constructed was published, allegedly written by the chatbot Racter (though the program as released would not have been capable of doing so).
Chatbots could be used as weapons on the social networks such as Twitter or Facebook. An entity or individuals could design create a countless number of chatbots to harass people. They could even try to track how successful their harassment is by using machine-learning-based methods to sharpen their strategies and counteract harassment detection tools.
Earlier, I made a rather lazy joke with a reference to the Terminator movie franchise, in which an artificial intelligence system known as Skynet becomes self-aware and identifies the human race as the greatest threat to its own survival, triggering a global nuclear war by preemptively launching the missiles under its command at cities around the world. (If by some miracle you haven’t seen any of the Terminator movies, the first two are excellent but I’d strongly advise steering clear of later entries in the franchise.)
ELIZA's key method of operation (copied by chatbot designers ever since) involves the recognition of clue words or phrases in the input, and the output of corresponding pre-prepared or pre-programmed responses that can move the conversation forward in an apparently meaningful way (e.g. by responding to any input that contains the word 'MOTHER' with 'TELL ME MORE ABOUT YOUR FAMILY'). Thus an illusion of understanding is generated, even though the processing involved has been merely superficial. ELIZA showed that such an illusion is surprisingly easy to generate, because human judges are so ready to give the benefit of the doubt when conversational responses are capable of being interpreted as "intelligent".