Keyword  plays a vital role  not only in quantity but as well as the quality  – i.e. if you have more keywords in the page title, the headings, the first paragraphs – this counts more than  if you have the same number of  keywords at the bottom of the page. The reason is that the URL (Uniform Resource Locator or the domain name ), html file names and site directory names, the page title, the headings for the separate sections of the page  are more important than ordinary text on the page if you consider SEO .If you have the same keyword density as your competitors but you have keywords in the URL definitely you are the winner . At the same time you must be very careful that to choose the keyword in the domain the domain name become longer so as a result it would be very difficult to remember the domain name for your  potential customer. So sometimes it is better to concentrate on the domain name so it become shorter to remember which ultimately add the retention value of your site and products .  File names and directory names are also important because  search engines will give preference to pages that have a keyword in the file name. The page title and headings are two other areas of concentration for seo (search engine optimization). Never leave any page untitled and always provide a relevant title in that page which truly reflect the contents of that page . The headings of different sections of your website should contain proper keywords for betterment f SEO but to become over concentrated for search engine optimization  a company must maintain the limit of seven to eight words maximum for a normal heading otherwise the visibility may hamper for that seo enabled site.