A search algorithm is an algorithm that finds a file with specified properties within a database of filesÂ that are stored on a computer system. In its most basic form a search algorithm is a procedure or setÂ of steps for solving a particular problem by using the problem as input and returning a solution. InÂ relation to search engines, search algorithms are used to rank information on the Web.
In the past, search algorithms were based on complex mathematical formulas. By using searchÂ algorithms, a search engine could determine how many links a website had, how long users typicallyÂ spend on the website, the number of times a keyword or phrase appears on a website and theÂ density of those keywords or phrases. The search engine then uses the output of search algorithmsÂ to give the website a ranking.
The problem with search algorithms that are solely based on mathematical formulas is that once theÂ formulas are revealed to the public, people can abuse the system by tricking the search engine intoÂ thinking their website is relevant. To counter this, search engines began using search algorithms that employ a combination of mathematical formulas and human input to determine the websiteâ€™sÂ ranking. These types of search algorithms are the focus of SEO Today.
These days, search algorithms are able to derive a ranking by looking at everything, from how longÂ the website has been on the Web to how many errors are encountered. New search algorithms areÂ even able to derive relationships between keywords, for example, the algorithm knows that theÂ keywords â€œFerrariâ€, â€œsports carâ€ and â€œautomobileâ€ are all related, and ranks the website accordingly.
Itâ€™s important to understand that each search engine uses different search algorithms and that theseÂ algorithms are usually kept secret, due to the competitive nature of the industry. Search EngineÂ Optimisation (SEO) experts are constantly trying to discover exactly how a search engine determinesÂ a websiteâ€™s page ranking, which leads to a lot of speculation, assumption and guesswork.