Crawlers rely upon keyword placement within the text of an article, and typically disregard images.<ref>{{cite book|title=Mastering Web 2.0: Transform Your Business Using Key Website and Social Media Tools|author=Susan Rice Lincoln|page=80|year=2009}}</ref> Text appearing at several key locations (such as the <code><[[HTML element#title_tag|title]]></code> and <code><[[HTML element#meta_tag|meta]]></code> tags of the page's code having unique text) gets special attention because search engines compare information found there with other pages to determine relevance. For example, a page's description meta tag gives Google and other search engines a summary of what the page is about.<ref>{{cite web|url=http://www.sibzsolutions.com/seo-services/seo-methodology.html|title=SEO Methodology|accessdate=26 June 2012}}</ref> SEO copywriters also strive for unique written content on the page, distinguishing it from similar pages competing for placement in the search results. Other factors that determine relevance during a search are the page's [[keyword density]], the placement of the keywords, and the number of links to and from the page from other pages.
