SEO Spider

Software developed and run by a search engine or other research entity that surfs the web without requiring human interaction. A spider gathers information from a web page, then follows one of its links to another page, gathers more data there, and so on until the entire site is indexed. (v.) This process of indexing, also known as "spidering" or "crawling." Unscrupulous spammers use spiders to harvest email addresses displayed on web pages or contained in their HTML code.