|“|| Many spambots crawl Web sites for login forms to create free e-mail addresses from which to send spam or to spam blogs, guestbooks, wikis, and forums to boost the search engine rankings of a particular Web site. * * *
Often, spambots ignore robots.txt and search for email addresses on the Web site and/or forms to which they can submit spam-related content. Spambots that merely scan the Web site typically do not affect its availability. Nevertheless, it may be beneficial to prevent them from harvesting e-mail addresses by performing address munging — displaying e-mail addresses in an alternative human-readable format, such as listing email@example.com as <name at mywww dot gov>. Unfortunately, these techniques do not stop all spambots. The best defense against address harvesting is not to display e-mail addresses.
Spambots searching for Web forms to submit spam-related content are a direct threat to the Web site. They can affect the organization’s image if visitors view the submitted content as an endorsement. They may also affect the Web site’s availability by making it difficult for users to find necessary content.