Search Engine Optimization (SEO) as a process is helping in the optimization of a website by improving both the internal and external aspect of a website. The aim would be to make sure that your website gets listed every time a user is trying to find some information. This can sometimes even be irrespective of what content your website offers. The optimization helps a site receive maximum traffic from search engines. The very idea of search engine optimization is to be found online when a particular keyword has been typed. A keyword can probably help you identify the content information you are looking for. Hence, keyword plays a very important role in helping your website being identified on search engines.
Often you will come across words such as search engine spiders when referring to the search engine optimization as a process, these search engine spiders basically help read content text with an accuracy of 100% and usually tend to miss important information featured in images, Flash or Java scripts. Several tests have to be run on the text content of the site ensuring a co-relation between the keywords in content. It has been a known fact lately that search engines like Google check for the "relevancy" of the information that is found on the websites linked with your website. In case the information on an existing site linked to your website co-relates directly to the information found on your site, it will be considered relevant and benefits the search engine rankings.