How do search engines rank websites?

Search engines use different criteria to rank websites and determine the most relevant website for each search term.

This criteria is the basis of the search engine ranking algorithm which drives the results. The algorithms are changed constantly as search engines try to find ways to provide users with more relevant results for their search terms.

Google users over 200 different factors in their search engine algorithm and have made a few major changes to the way websites are ranked in recent times.

A large part of search engine optimisation is keeping up with the most important algorithm changes and determining how this will impact individuals websites rankings.