Avoiding Damaging Internal Navigation Issues
The search engine spiders that crawl the internet are becoming incredibly advanced, although their basic function remains the same – they use links to traverse the internet, gathering data then recording that content in the search engine's index. Advances in technology are making the search engine spiders increasingly adept at gathering data from even the most unorganised websites. Despite this, there are several particularly problematic site elements that webmasters need to be aware of in order to ensure their website can achieve the maximum potential of search engine optimisation.
For the search engines to properly index the content on your website, they need to be able to be able to read and interpret the code that constructs a website. While the advances in search engine indexing are astonishing, there are still ways for content to be rendered in a way that makes it useful to the user, but uncrawlable for the search engine bots. Obviously these on-site elements want to be avoided.
Problematic Site Elements
The first onsite element to be wary of is the implementation of a 'site-search' feature and other web forms. For complex sites with hundreds or thousands pages of content, the internal 'search' feature is a great way to help users easily navigate to the information they are searching for quickly. The search
engines, however, will not be able to use this tool as they navigate websites by crawling links, and do not have the ability to submit forms or enter queries into search fields. While a 'Contact Us' page may consist of many of these forms, this is not a particularly substantial problem, as there is relatively little
value in these pages, but other form fields could potentially have a negative influence on the search engines interpretation of your site. The easiest way to combat this is to ensure there is at least one text link to the content that can be found by users completing a form or entering internal search queries.
Content in formats other than text can potentially cause problems for the search engines wanting to index your site. JavaScript embeds, Adobe Shockwave files, audio and video all render content in a way that is inaccessible to the search engines. So, any keyword directly placed in these non-text versions of content will have no influence on the way the search engines interpret your website. One solution is to use the ALT attribute. Through this attribute you can present a small amount of textual content to the search engines that describes what it is an image connotes, although this is quite a weak search signal. Another solution is to create a text link with targeted anchor text; generally a much more effective tactic. The same applies for JavaScript elements. Although JavaScript executions will very rarely interfere with the role of the search engine spiders, it can have an unwanted influence if one page relies on JavaScript to recall another page. The best way to counteract this is to ensure that a text link and content is accessible in the raw HTML code of a page.
There is also the possibility of creating a 'spider trap'. As discussed earlier, search engine crawlers discover content on your site by following links, and if there has been a glitch or programming error in your sites internal navigation system, then the search engine bots could get stuck in a loop, creating infinite pages that don't actually exist – this is a 'spider trap'. These can be caused due to several issues such as calendar links or huge numbers of ways in which content on your site is sorted or accessible. The search engines, for example, might come to your site and find thousands of pages of content when you only intended to create a few pages of true content. This can be fixed by using a robots.txt file to exclude the pages that are creating the 'spider traps' from being crawled and indexed by the search engines.
The final potentially harmful onsite element I'd like to discuss is the use of session ID's. This is a unique number assigned to a specific user by the hosting server for the duration of their visit, or session. The general consensus among the search engine optimisation community is that limiting the ability of users to view particular webpages due to session ID settings is a bad idea. This is because the search engine crawlers can't deal with session ID's properly, so any content only visible with particular a session ID may not be crawled and indexed by the search engine bots.
Hopefully these have made you aware of some of the issues and solutions that can be applied to internal website navigation issues. For the most effective SEO, websites need to be built to cater for search engines and users; finding the balance is the key to improving online visibility.
