“Search engines” is a generic term for huge relational databases that scour the Internet analysing web pages and logging information. They take two major forms - those that require human intervention and those that require non-human intervention.

Search engines that require human intervention employ editors who review and categorise the web sites that have been submitted for inclusion and decide if the listing will be accepted. Due to time constraints, they will normally only list one page from a complete website. Additionally, once a site is listed in a directory, getting an editor to change your listing or move you to another category can be almost impossible.

Popular human search engine sites are Yahoo, Dmoz, Google………

Non-human search engines are updated using a tool commonly referred to as a ‘spider’ or ‘robot’. Search engine spiders can scour hundreds of thousands of pages a day. Many of them will also follow the links on a page to find information independently. Thus, it is possible for your page to be indexed by a spider even if you have not submitted the page to the search engine. It is also possible that a spider will index and list every page on a site.

Popular spider based search engines are Lycos, Alltheweb, Hotbot, MSN, Excite….

Despite claims to the contrary, nobody has a magic formula to guarantee you top ranking with all of the search engines all of the time. Each search engines is different, and what may work well this week, might not work well the next. Additionally, the people who run the search engines will only give a general idea of how they actually rank sites. As a result, the field of search engine optimisation is very fluid and dynamic. It is a constant process of hypothesizing, submitting, monitoring, and fine-tuning. There are very few absolutes.