How Search Engines Work
Imagine the Internet as how it is described – the World Wide Web – a giant spider web (I hate spiders, but it is the best analogy). Every webpage (documents, PDF files, and images included) is an individual point on that web, and the paths that link all those points together are links. Search engines need a way to “crawl” through all of content on the web and index it for users to search, so they send out their “spiders” (also called crawlers or robots). These spiders travel from point to point on the web through the links we create.
As the spiders find all of the available pages, files, documents and information on the web, they also continuously sort and index all that information to later be recalled in searches. They analyze the text and code within every single file they come across, storing bits and pieces of it on their massive hard drives for later recall. All the major search engines have gigantic data centers all over the world in order to store all of this information with thousands of machines continually processing and evaluating the data to make your search results as quick and accurate as possible.
The results a search engine provides in a search are ranked based on both the relevance (is content on the page is clearly pertaining to what you searched for?) and the importance of the content (how popular the page is – the more popular, the better the content must be). These two rankings are determined by carefully crafted (and very secret) algorithms that makes each search engine unique. The are made up of hundreds of variables, or ranking factors, that judge where in the search results a page should come up. It should also be noted, that Google recently announced some changes to their algorithm that take into account when the content was posted or last updated, another reason people are turning more and more to blogging to keep their content relevant.
Each search engine has its own guidelines for best practices of content in a site. Here you can find the content quality guidelines from Yahoo, Bing, and Google. Even though they each have their own guides, they all have the same basic rule – build a useful, information rich site geared towards the user, not search engines, and don’t be deceptive with your content try to increase your rankings.
Here are a few more basic recommendations for creating your site and content:
- Each page should be accessible through at least one static text link.
- Do not include important content in images, search engines cannot read them.
- Make sure your title and ALT text is descriptive and pertinent to your content.
- Have links to other sites that are also pertinent to your site and content – but keep links on any given page down to a reasonable number.
- The number of relevant sites linking to your site is important.
- Update your content often.