Bots are used by search engines like Google and Bing to crawl online pages by moving between websites, gathering data about them, and indexing them. Search engine optimization, or SEO, is a technique used by online marketers to increase the visibility of their website in search engine results on Google, Bing, Yahoo, DuckDuckGo, and other search engines. Marketers efficiently communicate with search engines what their website is about and why it should rank highly in search engine results pages by using technical, on-page, and off-page SEO methods.