'bot (or agent)

On the Internet, automated piece of software that performs specific tasks. 'Bots are also known as agents or intelligent agents. On the World Wide Web, 'bots automate maintenance tasks such as indexing Web pages and tracing broken links. Search engines send out 'bots (also called ‘spiders’) to crawl through the Internet, compiling information on the Web addresses they visit. The information compiled by the spiders is used to rank Web sites in order of relevance when a user carries out a search using a search engine.

'Bots are commonly found on multi-user games where they maintain a constant level of activity even when few human users are logged on. They can also be found in chat environments where they can respond automatically to questions from users.