Dynamic Content and Menus

Search engines cannot read text that is dynamically created when a visitor asks for it. A search engine will follow all of the links it can see on a web site. But a search engine will not type in search terms in a "search box" to see what other content you have in your database. If you have a database driven web site you must have "hard coded" links to the data that the search engine can follow, or much of your web site will be not be indexed.

Search engines cannot read text embedded in JavaScript or any other scripting language that requires the user to do something (like choose from a drop down list of options) to get to new content. Therefore, most of the drop-down type navigation bars you see at the top of web sites are actually barriers to search engines. Unless a search engine spider sees an actual coded link you will lose them. This is actually the most common barrier we will see on a website because inexperienced web design personnel are unaware of the fact that search engines cannot read scripted menus.

As an aside, javascript drop down menus are usually also less human user-friendly due to the fact that they difficult to manually operate, and they provide no navigational reference point since the drop down 'snaps back up' disappearing as soon as it is clicked. While there are again various methods to "get around" this obstacle, these are stop-gap measures that can and should be avoided.

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