bingbot is a web-crawling robot, deployed by Microsoft to supply Bing (search engine). It collects documents from the web to build a searchable index for the Bing (search engine). It replaced msnbot as the main Bing Crawler on October 2010. A typical user agent string for bingbot is ” Mozilla/5.0 “. This appears in the web server logs to tell the webmaster who is requesting a file.