A number of common practices used by website developers result in reduced website visibility, the most common of these are listed and described below:• Websites constructed using HTML frames
• Web pages consisting mainly of Macromedia Flash generated code
• Web pages, especially home pages, consisting mainly of a large image map
• Incorrect HTML syntax
• Dynamic web pages
• Splash screens, used as the main element in a home page
• Hidden text
• Web pages containing off topic or irrelevant text
• Doorway pages
• Over optimised web pages
• Pages with duplicated content
Pages with HTML Frames are pages that are subdivided into separate, possibly scrollable areas. These have the advantage that a constant navigation area, or a constant page title area, can be displayed. However search engine indexers can get confused while attempting to crawl a site having framed pages as they are unable to determine which frame contains the main content of the page.
It is now possible to build complete web sites using Macromedia Flash. To the human these pages can look very attractive, incorporating every aspect of a website including site navigation into an interactive Flash graphic. However web spiders cannot retrieve any useful information from the Flash code within the HTML pages, making these sites very unattractive to search engines.