A.Programme called crawler follows, or "crawls", links throughout the Internet, grabbing content from sites and adding it to search engine indexes. Robots only can follow links from one page to another and from one site to another. That is the primary reason why links to your site (inbound links) are so important. Links to your website from other websites will give the search engine spiders more "food" to chew on. The more times they find links to your site, the more times they will stop by and visit. Google especially relies on its robots to create their vast index of listings.