Lead the spider to your content

Insuring that every page of your website gets found by the search engine spiders is probably the simplest thing you can do for your rankings. Not only will this increase the number of pages that a search engine credits your site with, but it also increases the number of phrases that your website has the potential to rank for.

We have seen websites that, once the search engines find all of their pages, you find that they are ranking on the first page and seeing traffic from phrases they never thought to even research or target.

This may not necessarily be the case for you however.  Having a larger site with more pages related to your content will boost the value of your site overall. You are offering this content to your visitors, so why hide it from the search engines ?

Pages can be hidden from search engines if the linking is done in a way that they cannot read. This is the case in many navigation scripts. If your site uses a script-based navigation system then you will want to consider the implementation of one of the internal linking structures.

Additionally, image-based navigation is spiderable however the search engines can't see what an image is and thus, cannot assign any relevancy from an image to the page it links to other than assigning it a place in your website hierarchy.