What Is SEO: How do Search Engines Decide Relevancy?

January 13, 2010

Point number four on the previous post (What is SEO (search engine optimisation)?) explained that search engines decide how to rank pages based on how relevant it feels it is for the searcher. So this blog post (second of six in the series) explains what is involved when search engines classify a page as ‘relevant’.  

When looking at a particular page, the search engines will look for key areas where they would expect the search query to be located – the title tag, meta description, heading tags and body copy. If a page is relevant to the query, it will most likely have that keyword or phrase featured in the above areas.

Search engines also base relevancy on how popular they feel your page is (yes, it’s like going back to school again – the popularity contest never ends!!). This is why links – and good quality links, are important. Search engines will look at the links pointing to a page and analyse the type of link (whether or not the anchor text is relevant to the search query), what else is said on that page (is there information and copy near the link that contains the query term? This is why lists and directories aren’t generally classed as high quality links). They also look at whether or not the page in question links back to the linking site (is it reciprocal?) and how trustworthy the linking site is (for example a public sector domain such as .gov is more trustworthy than a .net, and Wikipedia is more trustworthy than wikidirectory.biz etc…).

The search engines combine the outcome of these two factors with many other smaller aspects and filter the total results through their algorithm. The algorithm then decides the score for each page, and will then present the list of results in order of most to least importance.

So you why link building is such an important part of SEO. If you have thousands of other websites all linking to your site, then the search engines will assume that your site is extremely popular and must have a certain level of value. If all your links come from well respected and trustworthy sites, then the power of the link is even greater. However, if you have a thousand links all coming from low quality sites or link farms, the search engines are likely to recognise this and eliminate the value of those links (or they even penalise you for trying to cheat the system).

What makes a good quality link?

• The anchor text: Anchor text is the text the link is made from. For example: ‘SMEketing: Marketing agency working with businesses in the South’ has the word ‘SMEketing as the anchor text – this tells the search engine that the word ‘SMEketing’ is relevant to www.SMEketing.com. A better anchor text would be : ‘SMEketing: Marketing agency working with businesses in the South’ – this tells the search engines that www.SMEketing.com is relevant to SMEketing marketing agency, which is much better.
• Popularity of the site: As mentioned before, it’s all about popularity! A popular site has a high volume of quality more links pointing to them.
• Text around the link: If the link has text surrounding it that is on topic, that link will be deemed better than a link surrounded by other links, or text that is not relevant

The next post (3 of 6) will focus on keyword research and will be posted on Friday. In the meantime, you can view the first post here: What is SEO (search engine optimisation)?, or get in touch to find out how we can help boost relevant traffic numbers to your site – call us on 023 8083 7271.

Filed under: Search Engine Optimisation (SEO)

Tags: (SEO), search engine optimisation, Website ranking